Taking specific heat of lead as 0.128 J/gK = c
We have energy of ball at 7.00 meter height = mgh = 
When leads gets heated by a temperature ΔT energy needed = mcΔT
= 
ΔT
Comparing both the equations
= ΔT
ΔT = 0.536 K
Change in temperature same in degree and kelvin scale
So ΔT = 0.536 
<span>65W * 8h * 3600s/h = 1.9e6 J = 447 Cal </span>
As you coast down a long hill on your bicycle, potential energy from your height is converted to kinetic energy as you and your bike are pulled downward by gravity along the slope of the hill. While there is air resistance and friction slowing you down by a little bit, your speed increases gradually until you apply the brakes, causing enough friction to slow yourself and the bike to a stop at the bottom.
A roller coaster will have higher kinetic energy at the lower hill because it will have already been moving as opposed to the initial hill. But I'm not one hundred percent certain. You can always google this stuff, but I do know for sure that at the first hill, the roller coaster will have higher potential energy.
Hope this helps!
This is True
Kinetic energy is the energy of motion. The bicyclist is in motion as he pedals up the tall hill. Therefore, the bicyclist contains kinetic energy.
It doesn't matter. If the slides are truly frictionless, then
your kinetic energy at the bottom will be equal to the
potential energy you had at the top, no matter what kind
of route you took getting down.
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The only way I can think of that it would make a difference
would be if the shallow slide were REALLY REALLY long,
and you didn't have anything to eat all the way down.
Then you might lose some weight while you're on the slide,
and your mass might be less at the bottom than it was at the
top. Then, in order to have the same kinetic energy at the
bottom, you'd need to be going a little bit faster.
But if it takes less than, say, two or three days, to go down the
long, shallow slide, then this effect would probably be too small
to make any difference.
