Movement and position questions

Movement and position syllabus

Questions on movement and position can test recall, calculations, explanations, diagrams, data handling and practical skills. You should be able to:

• 1.3 plot and explain distance−time graphs
• 1.4 know and use the relationship between average speed, distance moved and time taken: average speed = distance moved / time taken
• 1.5 practical: investigate the motion of everyday objects such as toy cars or tennis balls
• 1.6 know and use the relationship between acceleration, change in velocity and time taken: acceleration = change in velocity / time taken a = (v − u) / t
• 1.7 plot and explain velocity−time graphs
• 1.8 determine acceleration from the gradient of a velocity−time graph
• 1.9 determine the distance travelled from the area between a velocity−time graph and the time axis
• 1.10 use the relationship between final speed, initial speed, acceleration and distance moved: (final speed)² = (initial speed)² + (2 × acceleration × distance moved) v² = u² + (2 × a × s)

How to answer movement and position questions

1. Read the axes and scales first: a distance–time gradient gives speed; a velocity–time gradient gives acceleration.
2. Find distance from the area under a velocity–time graph, splitting the area into simple shapes where helpful.
3. Convert quantities to consistent units before substituting into an equation, and include the final unit.
4. For practical improvements, name the change to the apparatus or method and explain the error it reduces.

Movement and position example questions and worked answers

These examples show how information in a diagram, graph or experimental context becomes part of a complete exam answer.

Example 1: Choosing a distance–time graph

June 2021 · Paper 1P · Question 4(b)

Question 1

The diagram shows a velocity-time graph for a car from the time the driver sees an obstacle in the road until the car comes to rest.

Which of these represents the distance-time graph for the car?

Final answer

A. The distance increases throughout, first at a constant rate and then at a decreasing rate until the car stops.

Mark scheme points

1. M1 Select option A.

Explanation

The gradient of a distance–time graph represents speed. The car moves at constant speed at first, so the graph rises steadily. As the car decelerates, its speed and the graph’s gradient decrease. When the car stops, the graph becomes horizontal.

Common mistakes

• Do not choose a straight rising graph for the whole journey: that would show constant speed, not deceleration.
• The distance should not jump suddenly, and it should keep increasing while the car is moving.

Example 2: Improving a falling-card experiment

June 2017 (R) · Paper 1P · Question 3(d)

Question 2

A student investigates the motion of a 10 cm square piece of card as it falls.

He attaches some weights to the bottom of the card to make sure it falls vertically.

The photograph shows the student releasing a card.

Give two ways that the student could improve the accuracy of his measurements.

Final answer

Move the distance scale closer to the card, and read the card’s height with your eye level with the scale to reduce parallax.

Other acceptable methods include using a clamp or consistent release mechanism, making sure the scale is vertical, or accounting for zero error. Any two methods are needed.

Mark scheme points

The two points below form one full-mark combination.

1. M1 Move the scale closer to the card, or use a ruler nearer the light gate.
2. M2 Read the height at eye level to avoid parallax.

Explanation

Bringing the scale closer to the card makes it easier to judge the card’s position against the scale. Reading at eye level avoids parallax: when viewed from above or below, the card can appear to line up with the wrong scale marking.

Common mistakes

• Saying only “repeat the measurements”, “reduce human error” or “improve precision” does not give one of the specific improvements credited here.
• For the eye-level improvement, state that it avoids parallax; simply saying “look carefully” is not specific enough.

Practise Movement and position questions

Build a focused practice set from this part of the Edexcel IGCSE Physics syllabus.