A ball is suspended by a thread from the ceiling of a car. The brakes are applied and the speed of the car changes uniformly from 36kmph to zero in 5s. The angle by which the ball deviates from the vertical (g=10ms−2) is :
We have,
36 kmph = 10 m/s
v=u+at
∴a=−105
∴a=−2m/s2
Also,
g=10m/s2
Net acceleration,
aT=√a2+g2
an angle of net acceleration,
tanθ=ag=210
∴θ=tan−1(15) with vertical