Question

A car travels along a straight road in the +x direction). When the car changes speed, it does so uniformly. The position of the car as a function of time is shown in the figure below. Position on x-axis (m) 0 1 2 3 4 7 8 9 10 11 5 6 Time (s) Select the appropriate choice for each statement. greater than the magnitude of the acceleration at Pis... that at R. qual to the speed at N is ... that at T. greater than the magnitude of the acceleration at T is ... that at S. equal to the speed at S is ... that at T. greater than the x-acceleration at P is ... 0. less than the speed at U is ... that at T. By extrapolating the straight sections of the graph, you can estimate the time during which the speed is changing. This, with the change in speed, lets you estimate the magnitude of the acceleration. Submit Answer Incorrect. Tries 5/10 Previous Tres

Answer 1

Sol:

In position-time graph, slope represents velocity and rate of change of slope represent acceleration means if slope changes more rapidly acceleration is greater.

Now by using these concepts.

The acceleration at P is negative and magnitude is less while the acceleration at R is positive and magnitude is greater. [Hence less than]

The speed at N is less than that at T. Because slope at N is less that that at T.

The magnitude of the acceleration at T is equal to that at S. Because slope is constant at both points hence acceleration is zero at T and S.

The speed at S is equal to that at T. Because slope is same at both the points.

The x-acceleration at P is less than 0. Because it is negative.

The speed at U is less than that at T. Because slope is less.