Forces

DASKEREL wrote this teaching and practice using Oak's sequence as a source. View the source lesson at Oak National Academy. Oak has not endorsed this material. Check Oak's terms and separate rights for third-party works.

Learning outcomes

Identify the two interacting objects in a force
Describe a change in speed, direction or shape without confusing motion with force

Vocabulary: force · interaction · newton · deformation · resultant

Retrieve previous learning

What can a push or pull do to a moving object?

Check: It can change the object's speed, direction or shape, depending on the other forces acting.

Learn the concept

A force is a push or pull arising from an interaction between two objects. A hand pushes a trolley; the hand and trolley are the interacting objects. Earth attracts the trolley through gravity. An explanation should identify the object exerting a force and the object receiving it. Saying simply that the trolley 'has force' hides the interaction and makes it difficult to draw a correct force diagram later.

A force may change an object's speed, direction or shape. A soft ball can flatten briefly when it hits a wall; a cyclist can turn even while maintaining a similar speed. The observation 'the cyclist turned' is evidence of a change in motion. Naming the physical interaction that caused the turn is an explanation and may require further evidence about tyres, road contact and steering.

An object can experience several forces at the same time. A book at rest on a table is pulled downward by Earth and supported upward by the table. These forces can balance. Motion alone does not prove a forward resultant force: a moving object may continue steadily when forces balance. An unbalanced resultant causes a change in motion, rather than being required for motion to exist.

Force is measured in newtons, symbol N. This unit belongs after a numerical reading, such as 3 N, and is different from kilograms, a unit of mass. When a question provides only an observation, avoid inventing an exact force size. State what can be inferred, what other forces may matter and what would need measuring before making a stronger claim.

Worked model

Choose a hand pushing a trolley and name the two interacting objects.
Describe the hand's force on the trolley as a forward contact push, measured in newtons if a value is provided.
Suppose the trolley speeds up from rest: identify an increase in speed as the observed change.
Check for friction and other forces before concluding the size or direction of the overall resultant.

Guided practice

A pupil says a ball rolling steadily must have a forward resultant force. What is the flaw?

Hint: Does steady motion involve a change in velocity?

Check the guided answer

Steady motion does not itself require a forward resultant. A forward resultant would make the ball accelerate; other forces must be considered.

Independent practice

Write your own response to every question before viewing the model answers. Your writing stays in this page session; this activity does not submit, store or grade it. Avoid including private information.

Find and correct a misconception

“A moving object must have an unbalanced force in the direction it travels.”

Correction: An unbalanced force changes velocity; balanced forces can accompany steady motion. The resultant direction is the direction of the change, not necessarily the current travel.

Extend and reflect

A ball turns around a corner while its speed stays similar. Has its motion changed?

Guidance: Yes. Velocity includes direction. Explain the turning interaction and avoid treating speed alone as a complete description of motion.

Where this lesson could lead · Combined Science: Trilogy GCSE → Daskerel Physical Sciences

This lesson practises: Identify the two interacting objects in a force. Scientific explanation, measurement and evidence support later laboratory, technical and quality work.

Next school subject: Combined Science: Trilogy GCSE. Check the subject and examination board that fit your school.
Later DASKEREL learning: Daskerel Physical Sciences. Explore further study and build evidence from practical work.
Later credential exploration: No subject-specific professional credential is mapped from this lesson. Explore the credential catalogue after choosing a later specialism.
Example career direction: Laboratory Data Analyst. Explore organisations and local support.

This is an exploratory route, not a promise of admission, a qualification, certification eligibility or employment. Years 7–9 learning is an early foundation; any later credential may require substantial study, experience or local approval.

Year 7 · Physics and motion · original lesson pack

DASKEREL beta · internal AI review pending

Contact and non-contact forces

DASKEREL wrote this teaching and practice using Oak's sequence as a source. View the source lesson at Oak National Academy. Oak has not endorsed this material. Check Oak's terms and separate rights for third-party works.

Learning outcomes

Classify a named interaction by contact
Distinguish gravity, magnetism and friction in one situation

Vocabulary: contact force · non-contact force · friction · support · magnetic force

Retrieve previous learning

What two objects interact when a hand pushes a trolley?

Check: The hand and the trolley interact; the hand exerts a push on the trolley.

Learn the concept

A contact force acts when the objects in the named interaction touch. A table supports a book, a hand pushes a door, and a rough surface exerts friction on a sliding box. Friction relates to relative movement, or attempted movement, at a contact. It does not simply point opposite every object's overall direction of travel in every situation.

A non-contact force can act across a gap. Earth pulls a falling ball gravitationally; one magnet may attract or repel another; charged objects may attract or repel through electrostatic interaction. Each force still has an object or system that exerts it. The word 'non-contact' describes the two interacting bodies, not whether the space between them contains air.

Classify the particular force rather than the whole event. A ball falling through air experiences Earth's non-contact gravitational pull while interactions with air produce resistance. A magnet moving over a table may experience magnetic force across a gap and friction where it touches the table. Both types can act on one object at once.

Material properties matter. A classroom magnet strongly attracts suitable iron or steel objects but does not noticeably pull every material. A wooden ruler near a magnet is not evidence that magnets are absent or that magnetic forces require contact. Compare like conditions and make a bounded claim about the tested material.

Worked model

Name Earth and a falling ball: the gravitational interaction acts without those two surfaces touching.
Name the ball and surrounding air: resistance arises through interactions with air.
Name a sliding block and table: friction acts at their touching surfaces.
Record non-contact gravity and contact air resistance or friction separately, because a single event may involve both.

Guided practice

A magnet attracts a steel clip across a small gap. Which force type is this?

Hint: Do the named magnet and clip have to touch?

Check the guided answer

Magnetic attraction is a non-contact force between the magnet and steel clip across the gap.

Independent practice

Write your own response to every question before viewing the model answers. Your writing stays in this page session; this activity does not submit, store or grade it. Avoid including private information.

Find and correct a misconception

“If gravity acts on an object, no contact force can act on it.”

Correction: Several forces can act together. A supported object experiences gravity and an upward contact force at the same time.

Extend and reflect

Why is a magnet's pull on steel different from the table's friction on the steel?

Guidance: Identify the two interaction pairs and state which needs surface contact; avoid claiming all materials respond equally to magnets.

Where this lesson could lead · Combined Science: Trilogy GCSE → Daskerel Physical Sciences

This lesson practises: Classify a named interaction by contact. Scientific explanation, measurement and evidence support later laboratory, technical and quality work.

Next school subject: Combined Science: Trilogy GCSE. Check the subject and examination board that fit your school.
Later DASKEREL learning: Daskerel Physical Sciences. Explore further study and build evidence from practical work.
Later credential exploration: No subject-specific professional credential is mapped from this lesson. Explore the credential catalogue after choosing a later specialism.
Example career direction: Laboratory Data Analyst. Explore organisations and local support.

This is an exploratory route, not a promise of admission, a qualification, certification eligibility or employment. Years 7–9 learning is an early foundation; any later credential may require substantial study, experience or local approval.

Year 7 · Physics and motion · original lesson pack

DASKEREL beta · internal AI review pending

Measuring forces with a newton meter

DASKEREL wrote this teaching and practice using Oak's sequence as a source. View the source lesson at Oak National Academy. Oak has not endorsed this material. Check Oak's terms and separate rights for third-party works.

Learning outcomes

Explain a safe supervised force measurement
Read equal scale divisions and report the result with appropriate units

Vocabulary: newton meter · scale division · zero error · range · parallax

Retrieve previous learning

What is the unit of force?

Check: The newton, abbreviated N.

Learn the concept

A spring newton meter relates the extension of its internal spring to a calibrated force scale. A teacher should select equipment with a suitable range and show how it is attached. Before measurement, check whether an unloaded meter reads zero. Do not pull past the maximum printed value; overload can damage the spring and make later readings unreliable.

The meter should be aligned with the intended pull, and the pupil should wait for a stable pointer when the task calls for a steady reading. Read at eye level to reduce parallax, the apparent shift caused by viewing a scale from the side. Record the numerical value and N. A force reading is not a mass reading in kilograms.

Work out the scale interval rather than guessing digits. If there are five equal divisions from 1 N to 2 N, each division is (2 - 1) ÷ 5 = 0.2 N. A pointer at the third division after 1 N reads 1.6 N. An analogue scale with 0.2 N markings does not justify reporting four decimal places without a stated estimation rule.

Repeated pulls may differ because of angle, speed, zero offset or surface condition. Record each reading and method before calculating a mean. A set of similar readings suggests repeatability, not necessarily accuracy: a mis-zeroed meter could give consistently biased results. Actual use of apparatus needs teacher supervision, safe attachment and an age-appropriate risk check.

Worked model

Check a hypothetical 0–5 N meter is unloaded at zero and the expected force is within its range.
Count five equal spaces between the 1 N and 2 N labels, giving 0.2 N per space.
At the third small mark after 1 N, calculate 1 + 3 × 0.2 = 1.6 N.
Record 1.6 N and state the scale's limit; do not invent a more precise value.

Guided practice

A 0–10 N meter has five equal spaces from 4 to 5 N. What is the reading two spaces after 4?

Hint: One newton divided by five spaces is 0.2 N per space.

Check the guided answer

The reading is 4.4 N: two spaces add 0.4 N to the 4 N label.

Independent practice

Write your own response to every question before viewing the model answers. Your writing stays in this page session; this activity does not submit, store or grade it. Avoid including private information.

Find and correct a misconception

“A steady pointer reading is automatically exact.”

Correction: A reading is constrained by range, calibration, scale precision and technique. Repeats can be consistent while biased.

Extend and reflect

How would a +0.2 N zero offset affect three otherwise similar readings?

Guidance: All displayed readings would be about 0.2 N too high unless corrected through an approved calibration method; agreement alone would not reveal the offset.

Where this lesson could lead · Combined Science: Trilogy GCSE → Daskerel Physical Sciences

This lesson practises: Explain a safe supervised force measurement. Scientific explanation, measurement and evidence support later laboratory, technical and quality work.

Next school subject: Combined Science: Trilogy GCSE. Check the subject and examination board that fit your school.
Later DASKEREL learning: Daskerel Physical Sciences. Explore further study and build evidence from practical work.
Later credential exploration: No subject-specific professional credential is mapped from this lesson. Explore the credential catalogue after choosing a later specialism.
Example career direction: Laboratory Data Analyst. Explore organisations and local support.

This is an exploratory route, not a promise of admission, a qualification, certification eligibility or employment. Years 7–9 learning is an early foundation; any later credential may require substantial study, experience or local approval.

Year 7 · Physics and motion · original lesson pack

DASKEREL beta · internal AI review pending

Represent forces with labelled arrows

DASKEREL wrote this teaching and practice using Oak's sequence as a source. View the source lesson at Oak National Academy. Oak has not endorsed this material. Check Oak's terms and separate rights for third-party works.

Learning outcomes

Draw forces acting on one selected object
Use arrow direction and relative length appropriately without mixing interaction partners

Vocabulary: force diagram · arrow · direction · scale · object

Retrieve previous learning

Can a book at rest have both gravitational and support forces?

Check: Yes. Forces can act while an object remains at rest if their effects balance.

Learn the concept

A force diagram begins by naming one object of interest. Draw an arrow for each force acting on that object. An arrow points in the direction of the force and carries a label, such as 'gravity on book' or 'support from table'. Its length may show relative size when a scale or clear comparison is provided; it is not just decoration.

For a book resting on a level table, draw a downward gravitational arrow and an upward support arrow on the book. If the forces balance, make the arrows equal length in a scaled or comparative sketch. The book also pushes on the table, but that force acts on the table and belongs on a separate diagram of the table.

For a box pushed right while sliding, include the hand's push to the right and friction from the floor to the left, as well as weight downward and floor support upward if the full situation is requested. A force diagram is a model: it should state whether air resistance and other effects are intentionally omitted.

An arrow drawn along the direction the object travels is not necessarily a force. A cart can travel right while an unbalanced force points left and slows it. Check the named cause and chosen object before deciding direction. Reserve resultant calculations for forces acting on the same object, and handle perpendicular directions separately from simple one-dimensional subtraction.

Worked model

Choose the resting book, not the table, as the object represented.
Draw and label Earth's gravitational force downward on the book.
Draw and label the table's support force upward on the book, equal in length if the forces balance.
Exclude the book's downward push on the table because that acts on a different object.

Guided practice

A pupil adds the book's push on the table to a diagram of forces on the book. Why remove it?

Hint: Which object receives that force?

Check the guided answer

The table receives the book's push. A diagram of the book includes forces acting on the book, not forces it exerts elsewhere.

Independent practice

Write your own response to every question before viewing the model answers. Your writing stays in this page session; this activity does not submit, store or grade it. Avoid including private information.

Find and correct a misconception

“Force arrows always point the way an object is currently travelling.”

Correction: Arrows show the directions of forces acting on the chosen object. A moving object may slow under a resultant opposite its travel.

Extend and reflect

How would you show a cart travelling right while a leftward resultant slows it?

Guidance: Keep a separate rightward motion description, draw the acting force arrows and resultant leftward, and explain the change in velocity.

Where this lesson could lead · Combined Science: Trilogy GCSE → Daskerel Physical Sciences

This lesson practises: Draw forces acting on one selected object. Scientific explanation, measurement and evidence support later laboratory, technical and quality work.

Next school subject: Combined Science: Trilogy GCSE. Check the subject and examination board that fit your school.
Later DASKEREL learning: Daskerel Physical Sciences. Explore further study and build evidence from practical work.
Later credential exploration: No subject-specific professional credential is mapped from this lesson. Explore the credential catalogue after choosing a later specialism.
Example career direction: Laboratory Data Analyst. Explore organisations and local support.

This is an exploratory route, not a promise of admission, a qualification, certification eligibility or employment. Years 7–9 learning is an early foundation; any later credential may require substantial study, experience or local approval.

Year 7 · Working scientifically · original lesson pack

DASKEREL beta · internal AI review pending

Reducing friction: plan and interpret a supervised practical

DASKEREL wrote this teaching and practice using Oak's sequence as a source. View the source lesson at Oak National Academy. Oak has not endorsed this material. Check Oak's terms and separate rights for third-party works.

Learning outcomes

Identify a fair comparison for a surface condition
Read fictional newton-meter measurements
State practical safety and interpretation limits

Vocabulary: independent variable · control variable · repeat · newton meter · risk assessment

Retrieve previous learning

What must be compared to decide whether friction has changed?

Check: Comparable measurements of the same kind of friction under controlled conditions, changing only the planned surface condition.

Learn the concept

A school may compare how a surface condition affects the force needed to pull a block steadily across a surface. The independent variable is the planned condition, such as a teacher-selected lubricant; the dependent reading is the pull measured in newtons. The block, load, surface, contact area, pull direction and approximate speed should otherwise be kept comparable. A single reading is weaker evidence than a set of repeats.

Any real investigation is teacher-led with an approved school risk assessment. The teacher selects safe materials, checks for spills and slip hazards, protects the newton meter from overload, supervises the pulling area and handles clean-up. This lesson provides no home procedure or advice to apply lubricants to floors. Written planning and fictional data cannot demonstrate safe practical competence.

Consider fictional steady-pull data. Condition A gives 4.1, 4.3 and 4.2 N; condition B gives 2.8, 2.9 and 2.7 N. All are within a fictional 0–10 N meter range and were taken with the same block, load and surface. The average for A is 4.2 N and for B is 2.8 N. The difference supports a lower measured pull under B in this model, subject to how consistently the block was pulled.

A steady pull can approximate the opposing sliding-friction force when the horizontal resultant is near zero. A jerky pull, acceleration, angled meter or changing contact can spoil that approximation. Record the meter's resolution and any unusual reading instead of hiding it. The practical does not prove that every lubricant, material or load behaves the same way, and it does not establish an exact friction force without method limits.

Worked model

State the question: how does one teacher-selected surface condition affect the steady-pull reading for the same block?
Keep load, contact surface, path, meter and pull direction comparable; change only the intended condition.
Use the fictional A and B readings to calculate A: (4.1 + 4.3 + 4.2) / 3 = 4.2 N and B: (2.8 + 2.9 + 2.7) / 3 = 2.8 N.
Report B as lower by 1.4 N in this small fictional dataset; qualify the steady-pull approximation and require supervised checks before any real experiment.

Guided practice

Why should a different block not be used only for condition B?

Hint: Think about changing more than one cause.

Check the guided answer

The block could alter contact and load, so a difference could not be attributed to the planned surface condition alone.

Independent practice

Write your own response to every question before viewing the model answers. Your writing stays in this page session; this activity does not submit, store or grade it. Avoid including private information.

Find and correct a misconception

“A smaller pull reading proves a lubricant always removes friction.”

Correction: It supports a lower reading under controlled conditions. Friction can remain, and the result depends on material, load and method.

Extend and reflect

How would you check whether condition B is consistently lower without performing an unsupervised experiment?

Guidance: Specify repeated teacher-run measurements, the same meter range and controlled load, and a plan to show the range rather than only a mean.

Where this lesson could lead · Combined Science: Trilogy GCSE → Daskerel Physical Sciences

This lesson practises: Identify a fair comparison for a surface condition. Scientific explanation, measurement and evidence support later laboratory, technical and quality work.

Next school subject: Combined Science: Trilogy GCSE. Check the subject and examination board that fit your school.
Later DASKEREL learning: Daskerel Physical Sciences. Explore further study and build evidence from practical work.
Later credential exploration: No subject-specific professional credential is mapped from this lesson. Explore the credential catalogue after choosing a later specialism.
Example career direction: Laboratory Data Analyst. Explore organisations and local support.

This is an exploratory route, not a promise of admission, a qualification, certification eligibility or employment. Years 7–9 learning is an early foundation; any later credential may require substantial study, experience or local approval.

Year 7 · Working scientifically · original lesson pack

DASKEREL beta · internal AI review pending

Reducing friction: analyse repeated measurements

DASKEREL wrote this teaching and practice using Oak's sequence as a source. View the source lesson at Oak National Academy. Oak has not endorsed this material. Check Oak's terms and separate rights for third-party works.

Learning outcomes

Compare repeated friction measurements fairly
Identify and investigate an unusual result
Separate precision from accuracy and qualify a conclusion

Vocabulary: mean · median · range · anomalous result · accuracy

Retrieve previous learning

What does a newton meter reading represent in a steady horizontal pull?

Check: It is the applied pull in newtons; with near-steady motion it may approximate opposing sliding friction, subject to method limits.

Learn the concept

A table of repeats helps distinguish a pattern from one accidental reading. For fictional condition A, the meter reads 3.1, 3.2 and 6.5 N; for B it reads 2.1, 2.0 and 2.2 N. Record units in the heading or each value. A's 6.5 N differs greatly from its other readings, but do not silently erase it. Check the original record, the meter range and the pulling method, then repeat under teacher supervision if possible.

A mean adds the readings and divides by their count. Including all A values gives (3.1 + 3.2 + 6.5) / 3 = 4.266... N, reported as about 4.3 N to match the 0.1 N readings; B gives 2.1 N. The median of sorted A readings is 3.2 N, and B's median is 2.1 N. Reporting both shows how one unusual A value affects the mean. Excluding it requires a documented reason, not simply a preferred conclusion.

A range is the highest minus the lowest reading: A has 3.4 N and B has 0.2 N. The tighter B readings are more repeatable in this small set, but a narrow range does not prove accuracy. An incorrectly zeroed meter could give nearly identical but biased readings. Check calibration, scale resolution, zero and consistent method before claiming a true value.

The fictional data support B having a lower typical measured steady pull under these stated conditions, especially by the medians. They do not prove that friction was eliminated or that B always wins under other loads and materials. A stronger report names the variable, controls, number of repeats, the unusual result and uncertainty. It separates observation from the proposed explanation that a changed surface condition reduced friction.

Worked model

Sort A as 3.1, 3.2, 6.5 N and B as 2.0, 2.1, 2.2 N; keep the same unit.
Calculate medians: A = 3.2 N and B = 2.1 N. Calculate means including all repeats: A is about 4.3 N and B is 2.1 N at the measurement precision.
Calculate ranges: A = 6.5 - 3.1 = 3.4 N and B = 2.2 - 2.0 = 0.2 N.
Flag A's 6.5 N for a method and record check; report a bounded comparison without automatically discarding it or treating a small range as accuracy.

Guided practice

Why is A's median 3.2 N while its mean is about 4.27 N?

Hint: Look at the largest value.

Check the guided answer

The 6.5 N reading pulls the mean upward, whereas the median is the middle of the sorted values.

Independent practice

Write your own response to every question before viewing the model answers. Your writing stays in this page session; this activity does not submit, store or grade it. Avoid including private information.

Find and correct a misconception

“A tight set of repeated readings proves the measurement is accurate.”

Correction: Repeatability describes spread; accuracy also depends on calibration, zero, resolution and whether the method measures the intended quantity.

Extend and reflect

How would a graph show the A and B datasets without hiding A's unusual reading?

Guidance: Plot all individual readings in newtons and mark the group medians. Explain that a teacher-reviewed repeat could test the unusual value.

Where this lesson could lead · Combined Science: Trilogy GCSE → Daskerel Physical Sciences

This lesson practises: Compare repeated friction measurements fairly. Scientific explanation, measurement and evidence support later laboratory, technical and quality work.

Next school subject: Combined Science: Trilogy GCSE. Check the subject and examination board that fit your school.
Later DASKEREL learning: Daskerel Physical Sciences. Explore further study and build evidence from practical work.
Later credential exploration: No subject-specific professional credential is mapped from this lesson. Explore the credential catalogue after choosing a later specialism.
Example career direction: Laboratory Data Analyst. Explore organisations and local support.

This is an exploratory route, not a promise of admission, a qualification, certification eligibility or employment. Years 7–9 learning is an early foundation; any later credential may require substantial study, experience or local approval.

Year 7 · Physics and motion · original lesson pack

DASKEREL beta · internal AI review pending

Energy stores in a changing system

DASKEREL wrote this teaching and practice using Oak's sequence as a source. View the source lesson at Oak National Academy. Oak has not endorsed this material. Check Oak's terms and separate rights for third-party works.

Learning outcomes

Identify energy stores in stated systems
Use joules for an energy quantity
Separate an energy store from a force or moving material

Vocabulary: energy · store · joule · kinetic · gravitational potential

Retrieve previous learning

What can a force do to an object's motion?

Check: A non-zero resultant can change its speed or direction; force is an interaction between objects.

Learn the concept

Energy is a quantity used to account for changes in a system. It can be described in stores associated with objects and their surroundings. A moving bicycle has a kinetic energy store; a lifted book and Earth form a system with a gravitational potential energy store. A stretched spring has an elastic store. Name the system and its condition before choosing a store, rather than attaching every store to every object.

Energy is measured in joules, J. A force is measured in newtons, N. These units are not interchangeable. A 5 N push describes an interaction, while a 5 J change describes an amount of energy transferred or stored. A force can be involved in a transfer, but the force itself is not an energy store and energy is not a substance that sits inside an arrow.

Imagine a book lifted from a low shelf to a higher shelf. Its gravitational potential energy store increases as work is done by a person. The person's chemical energy store decreases, and some energy is transferred to thermal stores. When the book falls, the gravitational potential store decreases and the kinetic store increases. On landing, more energy is transferred to surroundings, for example through heating and sound.

For a defined closed system, total energy is conserved even though the amounts in particular stores change. In a classroom story, a missing joule is often energy spread into surroundings outside the chosen boundary or a measurement limit, not energy destroyed. A store description should explain the before and after conditions; the physical interaction, such as a force or heating, explains how the change occurred.

Worked model

Choose the book, Earth, person and nearby surroundings as the system for a lifting example.
Before lifting, identify the book-Earth gravitational potential store as lower than it will be at the higher shelf.
During lifting, name the person's chemical store as one source and the increased gravitational potential store as one destination, with some thermal transfer.
After release, name the decreasing gravitational potential store and increasing kinetic store, then identify thermal and sound transfer on landing.

Guided practice

Which store increases when a stationary book is lifted higher, and which unit measures energy?

Hint: Consider the book-Earth system, then distinguish J from N.

Check the guided answer

The gravitational potential energy store increases; energy is measured in joules, J.

Independent practice

Write your own response to every question before viewing the model answers. Your writing stays in this page session; this activity does not submit, store or grade it. Avoid including private information.

Find and correct a misconception

“A force is a type of energy store and energy vanishes when motion stops.”

Correction: Force is an interaction measured in newtons. Energy is a conserved quantity measured in joules; motion energy can transfer to thermal stores and sound.

Extend and reflect

Why is 'the book has energy' less useful than a before-and-after store account?

Guidance: Identify the book-Earth system, its change in height and possible transfers to surroundings. Avoid inventing numerical joules without supplied data.

Where this lesson could lead · Combined Science: Trilogy GCSE → Daskerel Physical Sciences

This lesson practises: Identify energy stores in stated systems. Scientific explanation, measurement and evidence support later laboratory, technical and quality work.

Next school subject: Combined Science: Trilogy GCSE. Check the subject and examination board that fit your school.
Later DASKEREL learning: Daskerel Physical Sciences. Explore further study and build evidence from practical work.
Later credential exploration: No subject-specific professional credential is mapped from this lesson. Explore the credential catalogue after choosing a later specialism.
Example career direction: Laboratory Data Analyst. Explore organisations and local support.

This is an exploratory route, not a promise of admission, a qualification, certification eligibility or employment. Years 7–9 learning is an early foundation; any later credential may require substantial study, experience or local approval.

Year 7 · Physics and motion · original lesson pack

DASKEREL beta · internal AI review pending

Track energy transfers when forces act

DASKEREL wrote this teaching and practice using Oak's sequence as a source. View the source lesson at Oak National Academy. Oak has not endorsed this material. Check Oak's terms and separate rights for third-party works.

Learning outcomes

Track a before-and-after energy account
Identify a physical mechanism for a transfer
Apply conservation without claiming every transfer is useful

Vocabulary: transfer · mechanism · kinetic store · thermal store · conservation

Retrieve previous learning

How is a force different from an energy quantity?

Check: A force is a push or pull interaction measured in newtons; energy is a quantity tracked across stores and transfers, measured in joules.

Learn the concept

An energy account starts with a defined system and compares conditions before and after a change. When a cyclist brakes, the bicycle's kinetic energy store decreases; thermal stores of brake parts, wheel, tyres, road and surrounding air can increase. Saying 'energy is used up' hides these destinations. The total energy of a sufficiently complete closed system remains constant even when energy spreads into less useful forms.

The physical mechanism still matters. Brake friction acts between brake components and the rotating wheel, opposing wheel rotation. The tyre-road interaction and other resistive forces contribute to slowing the whole bicycle. These forces describe how motion changes and energy is transferred; the word energy alone does not explain the intermediate steps. A diagram should distinguish force arrows from energy-transfer arrows.

A stretched elastic band released under safe, teacher-approved conditions can transfer energy from its elastic store to a moving object's kinetic store, then to thermal stores and sound. This is an explanation, not a direction to launch objects. A written model can be assessed here; any physical demonstration needs an adult-approved setup and risk check. Avoid implying that all energy becomes useful motion.

Consider a fictional accounting model with 100 J initially in a moving system. After braking, 0 J remains in its kinetic store, 80 J has increased thermal stores in brake parts and wheel, and 20 J has increased thermal stores in road and air after any brief sound has dissipated. The model accounts for 100 J in total. It is simplified: real measurements and system boundaries may miss destinations, but missing measurements do not prove a failure of conservation.

Worked model

Define the bicycle, brake components, tyres, road and nearby surroundings as the system.
State that braking lowers the bicycle's kinetic energy store and that frictional interactions are physical mechanisms.
For the fictional 100 J account, add destinations 80 J + 20 J = 100 J and compare with the starting 100 J.
Explain that the total is conserved in the stated model while energy is spread; qualify any real-world measurement or boundary limit.

Guided practice

A toy car stops after rubbing on a rough surface. Does its kinetic energy disappear?

Hint: Include the surface and air in the system.

Check the guided answer

No. Its kinetic store decreases as energy transfers to thermal stores of the toy and surface and to the surroundings, with possible sound.

Independent practice

Write your own response to every question before viewing the model answers. Your writing stays in this page session; this activity does not submit, store or grade it. Avoid including private information.

Find and correct a misconception

“Friction stores energy, so braking makes the bicycle's energy disappear.”

Correction: Friction is an interaction that helps transfer energy. The kinetic store falls while thermal stores and other destinations increase; total energy is conserved for a complete closed system.

Extend and reflect

How would changing the system boundary affect a written energy account of braking?

Guidance: Compare counting only the bicycle with also counting road and air. Explain that energy may leave a narrow boundary while the total remains conserved in a sufficiently complete system.

Where this lesson could lead · Combined Science: Trilogy GCSE → Daskerel Physical Sciences

This lesson practises: Track a before-and-after energy account. Scientific explanation, measurement and evidence support later laboratory, technical and quality work.

Next school subject: Combined Science: Trilogy GCSE. Check the subject and examination board that fit your school.
Later DASKEREL learning: Daskerel Physical Sciences. Explore further study and build evidence from practical work.
Later credential exploration: No subject-specific professional credential is mapped from this lesson. Explore the credential catalogue after choosing a later specialism.
Example career direction: Laboratory Data Analyst. Explore organisations and local support.

This is an exploratory route, not a promise of admission, a qualification, certification eligibility or employment. Years 7–9 learning is an early foundation; any later credential may require substantial study, experience or local approval.

Year 7 · Physics and motion · original lesson pack

DASKEREL beta · internal AI review pending

Balanced forces and one-dimensional resultants

DASKEREL wrote this teaching and practice using Oak's sequence as a source. View the source lesson at Oak National Academy. Oak has not endorsed this material. Check Oak's terms and separate rights for third-party works.

Learning outcomes

Calculate a one-dimensional resultant with direction
Distinguish the direction of a change in motion from the direction of travel

Vocabulary: resultant force · balanced forces · unbalanced forces · velocity · acceleration

Retrieve previous learning

What must all force arrows in one object diagram have in common?

Check: They represent forces acting on that same chosen object.

Learn the concept

The resultant force combines all forces acting on one object, accounting for direction. Along one straight line, add forces in the same direction and subtract those in opposite directions. If a box experiences 5 N right and 3 N left, the resultant is 2 N right. State the direction: '2 N' alone leaves the physical conclusion incomplete.

Equal and opposite forces on the same object balance. A 4 N pull right and 4 N pull left give a zero resultant. The object can remain at rest or continue with steady velocity; zero resultant means there is no change in velocity under the simple model. It does not mean no forces act, nor does it always mean the object is stationary.

An unbalanced resultant can change speed or direction. A cart travelling right can have a 2 N resultant left and slow while still travelling right for a time. The resultant's direction describes the direction of acceleration or change in velocity, not necessarily the current direction of movement. Avoid writing 'left force means moving left' without initial-motion information.

The subtraction rule applies only to forces along one line. Upward support and downward weight may balance while a horizontal push remains unbalanced; handle each direction separately. Forces in an action–reaction pair act on different objects, so do not cancel them within one object's resultant. Quantitative acceleration is beyond this qualitative Year 7 check.

Worked model

Choose one box and list only the forces acting on that box: 7 N right, 2 N right and 4 N left.
Add the rightward forces: 7 + 2 = 9 N right.
Subtract the opposing leftward force: 9 - 4 = 5 N right.
Interpret this as an unbalanced rightward resultant that can change velocity rightward, without asserting the box is already moving right.

Guided practice

A cart has 6 N right and 6 N left. What is its resultant and what could it be doing?

Hint: Equal opposite forces on the same cart cancel.

Check the guided answer

Its resultant is 0 N. It could remain still or move with steady velocity; the forces do not change its velocity.

Independent practice

Write your own response to every question before viewing the model answers. Your writing stays in this page session; this activity does not submit, store or grade it. Avoid including private information.

Find and correct a misconception

“The resultant always points in the direction of an object's current travel.”

Correction: It points in the direction of acceleration or change in velocity. An object can still travel one way while slowing under a resultant the other way.

Extend and reflect

A box has 5 N right, 5 N left, 3 N up and 3 N down. What can you infer from this simplified diagram?

Guidance: Both horizontal and vertical resultants are zero. State that the box may remain still or continue with steady velocity, rather than inferring rest from balanced forces alone.

Where this lesson could lead · Combined Science: Trilogy GCSE → Daskerel Physical Sciences

This lesson practises: Calculate a one-dimensional resultant with direction. Scientific explanation, measurement and evidence support later laboratory, technical and quality work.

Next school subject: Combined Science: Trilogy GCSE. Check the subject and examination board that fit your school.
Later DASKEREL learning: Daskerel Physical Sciences. Explore further study and build evidence from practical work.
Later credential exploration: No subject-specific professional credential is mapped from this lesson. Explore the credential catalogue after choosing a later specialism.
Example career direction: Laboratory Data Analyst. Explore organisations and local support.

This is an exploratory route, not a promise of admission, a qualification, certification eligibility or employment. Years 7–9 learning is an early foundation; any later credential may require substantial study, experience or local approval.

Year 7 · Physics and motion · original lesson pack

DASKEREL beta · internal AI review pending

Friction between contacting surfaces

DASKEREL wrote this teaching and practice using Oak's sequence as a source. View the source lesson at Oak National Academy. Oak has not endorsed this material. Check Oak's terms and separate rights for third-party works.

Learning outcomes

Identify the two surfaces in a friction interaction
Draw friction opposite relative sliding
Distinguish a useful reduction of friction from a claim of zero friction

Vocabulary: friction · contact · relative motion · surface · resistance

Retrieve previous learning

What is a contact force?

Check: A force arising when two objects touch, such as a surface pushing or rubbing against another surface.

Learn the concept

Friction is a contact interaction between surfaces. If a block slides right relative to a table, the table exerts sliding friction left on the block. Name both objects and the object receiving the force before drawing an arrow. Friction need not point opposite the object's motion relative to the room in every situation: the important comparison is motion, or tendency to move, relative to the contacting surface.

Microscopic surface features and interactions can resist sliding. A rougher surface may produce more friction in a particular comparison, but friction depends on the pair of surfaces and conditions, not on one material label alone. Pressing surfaces together more strongly may also change the interaction. A drawing of jagged surfaces is a useful model, not a literal scale picture of every contact.

Friction can be useful. A shoe's grip helps a walker push against the ground, and brakes use friction to change wheel motion. It can also make machines warm and wear over time. Lower friction may help a moving mechanism, but zero friction should not be inferred simply because a surface looks smooth or a lubricant was added. Design decisions need evidence and attention to safety.

Distinguish a friction force from a resultant. A moving block can have a rightward push and leftward friction at the same time; the difference determines the horizontal resultant. If the block moves steadily during an idealised pull, the horizontal forces may approximately balance. Real measurements can fluctuate, so a steady pointer is an approximation rather than proof of perfect balance.

Worked model

Choose the sliding block as the object whose forces are being described.
Identify the block-table contact and state that the block slides right relative to the table.
Draw the table's friction force on the block to the left and label it in newtons if a magnitude is supplied.
If a 5 N rightward pull and 3 N leftward friction both act on the block, calculate a 2 N rightward horizontal resultant without claiming the block already moves right.

Guided practice

A crate slides left across a floor. Which way does the floor's sliding-friction force on the crate point?

Hint: Compare the crate's motion relative to the floor.

Check the guided answer

It points right, opposite the crate's sliding relative to the floor.

Independent practice

Write your own response to every question before viewing the model answers. Your writing stays in this page session; this activity does not submit, store or grade it. Avoid including private information.

Find and correct a misconception

“Friction always points opposite an object's travel through the room.”

Correction: Sliding friction opposes relative sliding at the particular contact. First identify both surfaces and which object receives the force.

Extend and reflect

Why might adding lubricant to a hinge be useful but adding it to a staircase be hazardous?

Guidance: Compare the desired contact interactions and include a slip risk. Do not treat one lower-friction condition as universally better.