Atennis ball is hit straight up at 20 m/s from the edge of a sheer cliff. some time later, the ball passes the original height from which it was hit. (ignore the effects of air resistance.) (a) how fast is the ball moving at that time? m/s (b) if the cliff is 50 m high, how long will it take the ball to reach the ground level? s (c) what total distance did the ball travel? m

a) 20 m/s

b) 5.83 seconds

c) 90.78 m

Explanation:

t = Time taken

u = Initial velocity = 20 m/s

v = Final velocity

s = Displacement

a = Acceleration due to gravity = 9.81 m/s²

a)

Time taken to reach maximum height is 1.22 seconds

So, the stone would travel 20.39 m up

s = 20.39 m

The ball is moving a 20 m/s at the time the ball passes the original height from which it was hit

b) Total height stone would fall is 20.39+50 = 70.39 m

Time taken by the ball to travel 70.39 m is 3.79 seconds

Total time taken by the ball to reach the ground from the time it left the person's hand is 2.04+3.79 = 5.83 seconds.

c) The ball travelled a distance of 20.39+50+20.39 = 90.78 m

like poles repel so keep pushing north to north and repels funny to see this

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me