a motor car is going due north at a speed of 50 km/h.it makes a 90 o left turn without changin its speed the change in velocity of the car is ?
(The bold letters represent vector quantities)
Initial velocity of the car is, v1 = 50 km/h towards north.
Final velocity of the car is, v2 = 50 km/h towards west.
Change in velocity, ∆v = v2 – v1
Magnitude of the change is,
|∆v| = (v22 + v12 – 2 v1 v2 cos900)1/2 = 70.71 km/h
The direction of this change is φ w.r.t the initial direction,
= tan-1 (-1)