Motion
Overview
A delivery van leaves a depot at half past seven and returns four hours later. Nobody followed it. Nobody watched it park, pull away, sit in traffic or take the long way round the ring road. Yet the tracker in the cab hands the depot manager a single line on a chart, and from that line alone she can say when the van was moving, when it stopped, which leg of the journey was the fastest and how far it went in total. The line is a distance-time graph, and reading one is a skill you can learn in an afternoon and use for the rest of your life.
This lesson teaches you to read that line and to do arithmetic with it. You will meet the one equation the Physics Equation sheet prints for this topic, learn why physicists insist on two words for going fast rather than one, and find out how a slope on a piece of graph paper turns into a number in metres per second. By the end you will be able to look at a set of coordinates you have never seen before and describe the journey they record, which is exactly what the physics paper will ask you to do, on both tiers.
Objectives
- If an object moves in a straight line, its distance from a certain point can be represented by a distance-time graph.
- The speed of the object can be calculated from the gradient of a distance-time graph.
- The velocity, v, of an object is its speed in a given direction and is given by the equation: where s is the displacement and t is the time taken.
- This equation can also be used to calculate the average speed of objects undergoing non-uniform motion.
Mind map
This topic is mapped out so you can see how the ideas connect.
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Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Motion. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- Which of these quantities is a vector? A. Distance B. Speed C. Time D. Velocity Answer: D
- What does the gradient of a distance-time graph represent? A. The acceleration of the object B. The speed of the object C. The distance travelled by the object D. The total time of the journey Answer: B
- A distance-time graph for an object is a horizontal straight line for 20 seconds. What is the object doing during those 20 seconds? A. Moving at a constant speed B. Speeding up C. Slowing down D. At rest Answer: D
- A tram travels at a constant velocity of 12 m/s for 90 s. How far does it travel in that time? A. 7.5 m B. 102 m C. 1080 m D. 1350 m Answer: C
- The equation v = s / t is rearranged to make t the subject. Which is correct? A. t = v x s B. t = s / v C. t = v / s D. t = s x v Answer: B
Work through these questions in the app
Work through these questions in the app
Recommended Books
Practice Mock Questions
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