Jenny asks…can you guys answer about physics? here's the details..?1. A boy lifts a 2kg rock 1m above the ground. He then allows it to fall.
m=mass g=9.8 h=height v=velocity w=work f=force d=distance
pot energy=mgh
kin enrgy = 1/2 m x v square
(if the object were initially moving)w= change in kin energy(final minus initial)
w= fd
f= mg
w=fh
efficiency= w output/w input x 100%
(if this is not complete can you pls search for the formula)
w = change in energy
power=w/time
actual mech.
