U = m g h = potential energy above that at h = 0
where
m is mass
g is acceleration of gravity, about 9.81 m/s^2 on earth
h is height above reference plane, in this case the water surface would do.
The lower he goes, the less gravitational potential energy he has.
1. The diver has the least gravitational potential energy at position (1point)
[Shows picture of a diver jumping from a plank/diving board]
A.1 [On the board getting ready to jump] (My answer)**
B.2 [In the air at the peak of his jump hight]
C.3 [In the middle of falling from peak hight and falling into the water]
D.4 [In the water/end of fall] (Maybe correct)
My reasoning: I remember reading something about how gravitational potential energy is like dropping a pencil on your desk. The pencil has the most amount of potential energy when it is in the air rather than when it is on the table. So by that, it would make sense if the answer was A because he is on the plank and is not in the hands of gravity.
10 answers
( and the faster he falls)
v = sqrt (2 g h) if he falls distance h
because
kinetic energy = (1/2) m v^2
Ke gained = Pe lost
m v^2 = 2 m g h
v^2 = 2 g h
v = sqrt (2 g h) if he falls distance h
because
kinetic energy = (1/2) m v^2
Ke gained = Pe lost
m v^2 = 2 m g h
v^2 = 2 g h
Correct, but does that also apply to the start of the jump?
Yes, up on the board you have lots of potential energy.
If you fall you lose potential energy as you gain kinetic.
Your least potential energy is as you hit the water.
The higher the more U. B is it.
He is stopped at the peak of the jump. No kinetic, all potential.
Before he jumps he is stopped, but he uses his muscles and the Wheaties in there to jump higher still increasing total mechanical energy :)
If you fall you lose potential energy as you gain kinetic.
Your least potential energy is as you hit the water.
The higher the more U. B is it.
He is stopped at the peak of the jump. No kinetic, all potential.
Before he jumps he is stopped, but he uses his muscles and the Wheaties in there to jump higher still increasing total mechanical energy :)
Remember they asked for the "least" U. That is when he is lowest.
If you are way up on a ladder you have lots of potential energy compared to what you had at ground level. If you fall you convert that potential energy to kinetic. When you hit you use that kinetic energy to heat up the mush that remains of your muscles and bones.
Alright, tanks!
Um... does anyone know the answers? xD
Answers plz
damn I'm really bout to fail
83 answers