The displacement–time behaviour of a particle is described qualitatively as follows:…
PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
The displacement–time behaviour of a particle is described qualitatively as follows:
• From t = 0 to t = 3 s the displacement increases with a curve that gets steeper with time.
• From t = 3 s to t = 7 s the displacement increases linearly.
• From t = 7 s to t = 10 s the displacement still increases but the curve gradually flattens until it becomes horizontal at t = 10 s.
(i) For each of the three intervals state whether the acceleration is positive, zero, or negative, giving reasons from the wording of the description.
(ii) Sketch a qualitative velocity–time graph corresponding to the motion over the 10 s. Label the important points and shapes clearly.
(iii) On your velocity–time graph, indicate the interval whose area contributes the largest share to the total displacement. Justify your answer.
(iv) Does the particle ever move back toward the starting point? Explain your reasoning based on the graph you have drawn.