A commuter train’s velocity (in meters per second) is modeled for seconds by the…
PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A commuter train’s velocity v (in meters per second) is modeled for 0≤t≤9 seconds by the piece-wise linear function described below. The graph of v versus t is a sequence of straight-line segments joining the points
(0,0),(3,9),(5,9),(7,3),(9,0).
(a) Using the information given, compute the train’s average acceleration on the interval [0,3].
(b) Compute the average acceleration on the interval [5,9].
(c) On which of the two intervals, [0,3] or [5,9], does the train experience the greater magnitude of average acceleration? Justify your answer numerically and verbally.
(d) Identify an interval of length 2 seconds within 0≤t≤9 on which the sign of the average acceleration differs from your answers in parts (a) and (b). Support your choice with appropriate calculations.