Question

Question
A body is projected horizontally from the top of a tower with velocity 30m/s. If g=10m/s^2 the velocity of that body after 3seconds is .

Answer 1

Answer:

30√2 m/s

Explanation:

This is a case of horizontal projectile.

Initial velocity is completely along the horizontal. Therefore, the vertical component of this initial velocity is zero.

Now, after 3 seconds, the body will have a certain horizontal as well as a vertical component of velocity.

The horizontal component of velocity after 3 sec will be same as that of the initial velocity as there is no acceleration acting horizontally.

Therefore,

Vx = Ux = 30m/s

We know acceleration g does act along the vertical, hence the vertical component is not equal to the initial velocity.

Using equation of motion

V - u = at

Vy - Uy = gt

Vy - 0 = 10*3

Vy = 30m/s

We know that,

V = √Vx² + Vy²

= √900 + 900

= √1800

= 30√2 m/s

Please leave remarks if you understood the concept :)