Question

A ball is thrown at an angle of θ₀ = 60° above the horizontal with an initial speed of v₀ = 11.5 m/s. What will be the direction of the ball's velocity after 0.62 sec? Submit the angle between the velocity and the horizontal (in degrees).

The angle, θ = _____ deg.

At what time will the velocity of the ball make an angle 12° relative to the horizontal?

The time, t = _____  

Answer 1

see the diagram :

= 11.5 m/s

horizontal initial velocity =

vertical initial velocity =

Horizontal motion is non accelerated , so horizontal velocity remains constant.

at t = 0.62 s, let the angle made by velocity is theta.

.-----(i)

using kinematic equation along vertical :

----(ii)

divinding (ii) by (i) :

[answer]

when angle made by velocity with horizontal is 12 degree, then velocity is v2 and time taken is t2.

then,

vertical velocity : -----(iii)

horizontal velocity : -----(iv)

dividing (iii) by (iv) :

[answer]