Q1 of 43 Page 85

A motor car is going due north at a speed of 50 kmh–1. It makes a 90° left turn without changing the speed. The change in the velocity of the car is about:

Let the motor car start from A and take left from B.


Change in velocity =


=


(Since)


Using the Parallelogram Law of Vector addition:






Thus the magnitude of the change of velocity is


=


So, the direction is southwest.


More from this chapter

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2

Two objects are thrown up at angles of 45 and 60 respectively with the horizontal. If both objects attain the same vertical height, then the ratio of the magnitude of velocities with which these are projected is?

 3

A body is projected with a velocity of 40 ms–1. After 2s it crosses a vertical pole of height 20.4m. Calculate the angle of projection and horizontal range.

 4

The position coordinates of a projectile projected from the ground on a certain planet (with no atmosphere) are given by y = (4t – 2t2) m and x = 3t m where t is in seconds and point of projection is taken as origin the. The angle of projection of projectile with vertical is:-

a) 30° b) 37° c) 45° d) 60°

 5

An aeroplane is flying horizontally with a velocity of 600 kmhr–1 and at the height of 1960 m. When it is vertically at a point A on the ground, a bomb is released from it. The bomb strikes the ground at point B. The distance AB is