Question

a motor car is going due north at a speed of 50 km per hour it makes a 90 degree left turn without changing the speed the change in the velocity of the car is about?

Answer 1

given,

speed of the car = 50 km/hr

velocity of car  towards north = 50 km/hr

soln:

after a left turn of 90° it moves towards west with a velocity of 50 km/hr

now,

actual velocity towards south-west = √{(50)²+(50)²}

                       =50√2 km/hr

                       =70.5 km/hr towards north-west

therefore,

change in velocity of car =70.5 km/hr - 50 km/hr

                                         =20.5 km/hr