Question

a 1kg ball is thrown into the air with an initial velocity of 30 m/sec. how much kinetic energy does the ball have?


-how much potential energy does the ball have when it reaches the top of its ascent?

-how high into the air did the ball travel?

Answer 1

Assume potential energy on ground is zero.
Kinetic energy at 30 m/s
=(1/2)mv²
Potential energy at highest point, H from ground
=mgh
Equate energies,
mgh=(1/2)mv²
h=(1/2)mv²/mg
=v²/(2g)

Answer 2

A girl hold a 2kg netball at height of 1,5 m above the ground and throws is vertically upwards at a velocity of 4 m.s.it reaches its turning point and falls back to the ground