Question

A passenger in an open car travelling at 30 m/s throws a ball out over the bonnet. Relative to the car, the initial velocity of the ball is 20 m/s at 60^ to the horizontal. The angle of projection of the ball with respect to the horizontal road will be:

• A. tan⁻¹((2)/(3))
• B. tan⁻¹(√(3)4)
• C. tan⁻¹(4√(3))
• D. tan⁻¹((3)/(4))

Hint:

Always add velocities vectorially when motion is observed from a moving frame.

Answer 1

The Correct Option is B

Resolve velocity of ball relative to ground by vector addition of car velocity and ball’s velocity relative to car. Horizontal component = 30 + 20\cos60^, vertical component = 20\sin60^. Angle of projection is obtained using tanθ = (vy)/(vₓ).