Chapter 3, Problem 80A

To determine

To describe the changes in velocity and acceleration of the car while in first gear and whether acceleration is larger or smaller before and after changing the gear.

Explanation of Solution

Introduction:

The velocity of a body is the ratio of distance covered by the object with respect to time.

Acceleration of an object is the ratio of change in velocity with respect to time.

For the first gearfrom the velocity time graph,it is observed that the velocity increases fast initially and then there is slow increases in velocity.

As there is large change in velocity initially acceleration increases then acceleration decreases for small change in velocity.

So, to accelerate the car driver has to shift the gear.

From the graph, it is seen that near the point the slope of a graph less. At that point acceleration is low so driver has to shift to second gearthen the acceleration and slope of graph increases.

Hence, acceleration before changing the gear is smaller and after gear change itis larger.

CONCLUSION:

Acceleration before changing the gear is smaller and after gear change it is larger.