Question

subject (physics). A ball thrown vertically upwards returns to the
thrower in 20 seconda calculate the velocity
with which it was thrown and the
maximum height attained by the ball .​

Answer 1

Answer:

Acceleration = -g = -9.8

Time = t =20/2 = 10 sec           (because, 20 sec includes down trip as well)

Let initial velocity = u

Final velocity = v = 0m/s

Using v = u+at,

0 = u + (-9.8) * 10

u = 98m/s

Using 2as = v^2 - (u^2),

2*(-9.8)*s = 0^2 - (98^2)

-19.6s = -(98^2)

s = 480m