A metal ball of mass 2kg is allowed to fall freely from rest from height of 5m. Calculate potential energy it possesses and kinetic energy before it reaches the ground. What happens to mechanical energy of the ball after it hits the ground?

Answer 1

PE=2*9.8*heightinMeters joules
KE=1/2 *2*v^2

but v^2=vi^2+2 g* (5-h)

so KE= gh
total energy=PE+KE=2*9.8*h+2*9.8*(5-h)

= 2*9.8*5 joules

so it starts our at h=5 with all PE, then that energy changes to KE as it falls. At the bottom, it is converted to heat, sound.
=

Answer 2

100J