A 2kg object is released from rest from a height of 10m above the ground. Calculate
(i) the initial potential energy at a moment of release;
(ii) the kinetic energy at the moment it reaches 4m above the ground;
(iii) the speed of the object just before impact with the ground.
After the impact, the object finally comes to rest. Explain what happens the the lost kinetic energy.
[Take g=10m s^-1.]

Question

A 2kg object is released from rest from a height of 10m above the ground. Calculate
(i) the initial potential energy at a moment of release;
(ii) the kinetic energy at the moment it reaches 4m above the ground;
(iii) the speed of the object just before impact with the ground.
After the impact, the object finally comes to rest. Explain what happens the the lost kinetic energy.
[Take g=10m s^-1.]

anonymous · Answer

i) $PE = mgh$ where $h$ = 10 m
ii) $KE = mgh$ where $h$ = 6 m (the height it has fallen)
iii) $KE = mgh = \frac12mv^2$ where $h$ = 10 m
solve for v

anonymous · Answer

whats is this [math processing error]

anonymous · Answer

@broken_symmetry

anonymous · Answer

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anonymous · Answer

I guess the website doesn't work perfectly. My answer looked like this to me: