Motion, Forces and Energy

Worked examples (12)extended set

• 1Reading a measuring cylinder and finding a volume by displacement
• 2Measuring multiples: the diameter of one bead
• 3Multiple choice: which list contains only vectors?
• 4Scalars and vectors: definitions and classification
• 5Multiple choice: the volume of one small pellet
• 6Period of a pendulum from repeated timings
• 7Measuring the length of a pendulum accurately
• 8Resultant of two forces at right angles by calculation
• 9Resultant velocity by scale drawing
• 10Choosing a sensible number of significant figures
• 11A boat crossing a river
• 12The thickness and volume of one sheet in SI units

Model answers (6)

• ✓Model answer — Paper 2/4 short-answer style
• ✓Model answer — Paper 2 style
• ✓Model answer — Paper 6 / Alternative-to-Practical style
• ✓Model answer — Paper 6 style
• ✓Model answer — Paper 4 structured style
• ✓Model answer — Paper 6 / Alternative-to-Practical extended style

Worked examples (12)extended set

• 1Average speed for a journey that includes a stop
• 2Reading and interpreting a distance–time graph
• 3Multiple choice: an object falling without air resistance
• 4Defining acceleration and converting km/h to m/s
• 5A tram between two stops: describing motion and finding the distance
• 6Thinking and braking: a cyclist stops for a hazard
• 7Multiple choice: where is the acceleration changing?
• 8Drawing a tangent to find a changing deceleration
• 9Accelerating, decelerating and maximum speed on a distance–time graph
• 10Terminal velocity of a ball bearing falling through oil
• 11When does the car catch the cyclist?
• 12Falling on Earth and on another planet

Model answers (6)

• ✓Model answer — Paper 2/4 short-answer style
• ✓Model answer — Paper 2/4 style
• ✓Model answer — Paper 4 structured style
• ✓Model answer — Paper 4 graph style
• ✓Model answer — Paper 4 extended-explanation style
• ✓Model answer — Paper 4 multi-part structured style

Worked examples (12)extended set

• 1Weight from mass, and mass from weight
• 2Defining mass, weight and gravitational field strength
• 3Multiple choice: which statements about weight are correct?
• 4Weight and mass of a satellite far from Earth
• 5A rover on different worlds
• 6Finding a mass with a top-pan balance
• 7Using a spring calibration graph to find an unknown mass
• 8Two blocks of the same size on force meters
• 9Weight as the force in a calculation: lifting a box
• 10A parachute load falling at constant speed
• 11Resultant force when weight is one of the forces
• 12Multiple choice: what does the balance reading tell you?

Model answers (6)

• ✓Model answer — Paper 2/4 short-answer style
• ✓Model answer — Paper 2/4 style
• ✓Model answer — Paper 4 structured style
• ✓Model answer — Paper 4 explanation style
• ✓Model answer — Paper 4 structured style
• ✓Model answer — Paper 4 multi-part structured style

Worked examples (12)extended set

• 1Stating the density equation and finding a volume
• 2Choosing apparatus for an irregular solid (multiple choice)
• 3Density in kg/m³ from dimensions in cm and mm
• 4Describing the displacement method
• 5Why a concrete canoe floats
• 6Which liquid floats on which (multiple choice)
• 7Density of a liquid from a balance and a measuring cylinder
• 8Density of one small object from a group of eight
• 9Density of a ball measured between two blocks
• 10Density from the gradient of a mass–volume graph
• 11How much gold is in an alloy bracelet?
• 12Separating container and liquid on a graph

Model answers (6)

• ✓Model answer — Paper 2/4 short-answer style
• ✓Model answer — Paper 2/4 style
• ✓Model answer — Paper 4 / Paper 6 style
• ✓Model answer — Paper 4 structured style
• ✓Model answer — Paper 6 / Alternative-to-Practical style
• ✓Model answer — Paper 6 / Alternative-to-Practical extended style

Worked examples (12)extended set

• 1What a resultant force can do
• 2Resultant force on a sledge (multiple choice)
• 3Spring constant from two loads (multiple choice)
• 4Spring constant and limit of proportionality from a graph
• 5Resultant force on an accelerating aircraft
• 6Released mass on a stretched spring
• 7Showing there is no resultant moment
• 8Using the weight of the rule itself
• 9Load–extension experiment: reading, extension and proportionality
• 10Force on a car going round a circular track
• 11A spring that is compressed as well as stretched
• 12Support forces on a loaded plank

Model answers (6)

• ✓Model answer — Paper 2/4 short-answer style
• ✓Model answer — Paper 2/4 style
• ✓Model answer — Paper 4 structured style
• ✓Model answer — Paper 4 structured style
• ✓Model answer — Paper 4 extended-explanation style
• ✓Model answer — Paper 6 / Alternative-to-Practical extended style

Worked examples (12)extended set

• 1Defining and calculating momentum
• 2Resultant force at constant velocity (multiple choice)
• 3Finding an unknown mass after the gliders stick
• 4Force needed to stop a drifting boat
• 5Bumper cars that lock together
• 6Impulse on a rebounding squash ball
• 7Final momentum after a kick (multiple choice)
• 8Force from a jet of water
• 9Two skaters push apart
• 10Testing conservation of momentum with light gates
• 11Resultant force from a momentum–time graph
• 12A ball bounces off a block, which then slides to rest

Model answers (6)

• ✓Model answer — Paper 2/4 short-answer style
• ✓Model answer — Paper 2/4 style
• ✓Model answer — Paper 4 structured style
• ✓Model answer — Paper 4 structured style
• ✓Model answer — Paper 4 application style
• ✓Model answer — Paper 4 multi-part structured style

Worked examples (12)extended set

• 1Energy stores of a swinging pendulum
• 2Which resources get their energy from the Sun? (multiple choice)
• 3Measuring the power of a student running upstairs
• 4Maximum height of a ball kicked upwards (multiple choice)
• 5Show that the braking force is about 250 N
• 6Launch speed from stored elastic energy
• 7Useful energy output of an electric kettle
• 8Energy used by a dehumidifier in kilowatt-hours
• 9Efficiency of a two-stage winch from a Sankey diagram
• 10Efficiency of a motor from an experimental graph
• 11Energy transferred when a ball bounces
• 12Roller-coaster speed with work done against friction

Model answers (6)

• ✓Model answer — Paper 2/4 short-answer style
• ✓Model answer — Paper 2/4 style
• ✓Model answer — Paper 4 structured style
• ✓Model answer — Paper 4 structured style
• ✓Model answer — Paper 4 structured style
• ✓Model answer — Paper 4 extended-response style

Worked examples (12)extended set

• 1Which person exerts the greatest pressure? (multiple choice)
• 2Why a dam is thicker at the bottom
• 3Pressure under the feet of a wardrobe
• 4The two ends of a drawing pin
• 5Rearranging the liquid pressure equation (multiple choice)
• 6Extra force on a submarine window
• 7Drinking through a straw (multiple choice)
• 8Why a heavy tractor sinks less than a car
• 9Measuring the pressure a student exerts on the floor
• 10Density of a liquid from a pressure–depth graph
• 11Pressure at the base of a tank of oil on water
• 12Greatest and least pressure under a brick

Model answers (6)

• ✓Model answer — Paper 2/4 style
• ✓Model answer — Paper 2/4 style
• ✓Model answer — Paper 4 explanation style
• ✓Model answer — Paper 4 structured style
• ✓Model answer — Paper 4 structured style
• ✓Model answer — Paper 4 multi-part structured style