Question

A ball is thrown vertically upwards return to the thrower in 20 second. Calculate the velocity with which it was thrown

Answer 1

Answer:-

U = 100 m/s

Given:-

Time of flight = 20s

V = 0m/s

g = 10 m/s

To find :-

The velocity with which it thrown

(u).

Solution :-

Let the initial velocity be u .

We know that, when a body is thrown upwards.

Time of ascent = Time of descent

Time of ascent = $\dfrac {20}{2}$

Time of ascent = 10s

Now, By using equation of motion

$\boxed{\sf{ V = u -gt}}$

Put the given value ,

$0 = u -gt$

$u = gt \\ u = 10 \times 10$

$u = 100 m/s$

hence, the initial velocity of ball is 100 m/s.