The figure below shows the velocity of a train as a function of time. (a) At wha
ID: 1407593 • Letter: T
Question
The figure below shows the velocity of a train as a function of time.
(a) At what time was its velocity greatest?
(b) During what periods, if any, was the velocity constant? (Enter these periods in the order in which they occur. Enter 0 in any unused answer boxes.)
(c) During what periods, if any, was the acceleration constant? (Enter these periods in the order in which they occur. Enter a 0 in any unused answer boxes.)
(d) When was the magnitude of the acceleration greatest?
The figure below shows the velocity of a train as a function of time 40 30 a 20 10 0 0 10 20 30 40 50 60 70 80 90 100 110 120 (a) At what time was its velocity greatest? 48 (b) During what periods, if any, was the velocity constant? (Enter these periods in the order in which they occur. Enter 0 in any unused answer boxes.) 90 s to 108 s to 0 (c) During what periods, if any, was the acceleration constant? (Enter these periods in the order in which they occur. Enter a 0 in any unused answer boxes.) s to 40 Xs to 0 (d) When was the magnitude of the acceleration greatest? 70Explanation / Answer
A) The velocity is at its maximum when the time is 48 s
Ans : 48 s
B) In the time period between 90 s and 108 s the velocity is a flat line. Hence there is no change in velocity.
Ans : 90 s - 108 s
C) In the time period between 0 s and 40 s the velocity is a straight line with positive slope. It means the acceleration is constant between 0 s and 40 s. Also in the time period between 60 s and the velocity is a straight line with negative slope. It means the acceleration is constant, ( the acceleration may have negative value, but it is constant)
Ans : 0 s - 40 s and 60 s - 80 s
D) The drastic change in acceleration happens in the period between 60 s to 80 s. Because the slope this segment is the greatest in magnitude. Since the mid point is 70 s the magnitude of slope is at its maximum at 70 s
Ans : 70 s