when an 81 kg adult uses a spiral staircase to climb to the second floor of his house, his gravitational potential energy increases by 2 X 10^3. by how much does the potential energy of an 18 kg child increase when the child climbs to the second floor?
a. 638 N
b. 478 N
c. 319 N
d. 532 N
e. 444 N
2007-03-04 16:09:41 · 5 answers · asked by tico 1 in Science & Mathematics ➔ Physics
Let's say adult dude starts of at 0 J of potential energy.
if after he climbs a certain height, h, he now has 2000 J of energy then he climbed
E/mg = 2000/81(9,8) = h = 2,519 m.
Now this friggin' kid starts off at 0 J of potential energy too.
Then when he climbs the this same height he gains
mgh = 18(9,8)2,519 = E = 444.352 Joules of potential energy
2007-03-04 16:23:46 · answer #1 · answered by Anonymous · 0⤊ 0⤋
Your units are inconsistent. How much does the adult's potential energy increase? Is that in mJ, kJ, J? Potential energy for the answer should not be in Newtons, which is a unit of force not energy.
2007-03-04 16:18:01 · answer #2 · answered by msi_cord 7 · 0⤊ 0⤋
I worked it by ratio and proportion and I got 444.
2007-03-04 16:32:29 · answer #3 · answered by Max 6 · 0⤊ 0⤋
why does it matter you sound like you already know the answer do you have some sort of a master plan
2007-03-04 16:13:59 · answer #4 · answered by blademan82002 2 · 0⤊ 0⤋
Posting your homework and getting others to do it is useless to your education and is also unethical. Grow up and take responsibility for your own education.
2007-03-04 16:28:56 · answer #5 · answered by smartprimate 3 · 0⤊ 1⤋