After the mass has fallen three-fourths of the way to the ground, its kinetic energy will be equal to
a. mgh/4
b. 3mgh/4
c. mgh
d. 4/3mg
2007-03-31 23:15:09 · 8 answers · asked by nina l 1 in Science & Mathematics ➔ Physics
Before release, the mass has potential energy of mgh. After falling 3/4 the way to the ground, it still has mgh/4 potential energy (i.e. a quarter of the original height) so the kinetic energy must be (mgh-mgh/4) = 3mgh/4.
2007-03-31 23:20:49 · answer #1 · answered by JJ 7 · 0⤊ 0⤋
This problem is based on law of conservation of energy
Loss in potential energy (PE) = Gain in Kinetic Energy (KE)
Loss in PE = mgh - 1/4*mgh = 3/4mgh = KE (initial KE =0 since V=0 intially)
2007-04-01 06:28:00 · answer #2 · answered by Making_Happy 4 · 0⤊ 0⤋
potential enegy=kinetic energy
so at the highest point the P.E is at its highest thus-->mgh
at three-fourths of the way the mgh is a fraction of what it used to be so it now mgh/4.
however since energy can't be created nor destroyed but can only be changed from one form to another.
the 3/4mgh were changed to kinectic energy.
so ans is b.
2007-04-01 07:19:32 · answer #3 · answered by cute-goddess 5 · 0⤊ 0⤋
b
kin en = the change in potential energy
2007-04-01 06:25:37 · answer #4 · answered by oracle 5 · 0⤊ 0⤋
3mgh/4
2007-04-01 07:35:34 · answer #5 · answered by LJUDAD 2 · 0⤊ 0⤋
b. 3mgh/4
2007-04-01 06:25:54 · answer #6 · answered by shaheer 2 · 0⤊ 0⤋
answer-option b
2007-04-01 06:20:28 · answer #7 · answered by Albert einstein 2 · 1⤊ 0⤋
none of these
2007-04-01 06:20:33 · answer #8 · answered by Imran 2 · 0⤊ 0⤋