Answer:
Emechanical=mgh+
mν²
Explanation:
The equation for the total mechanical energy is:
Emechanical=Epotential+Ekinetic
In which,
Epotential=mgh; m: mass of the body, g: gravity; h: height
Ekinetic=
mν²; m: mass of the body, ν: velocity of the body
So,
Emechanical=mgh+
mν²
Answer:
<em> think 2 also if not im so sorry but i think it is :)</em>
Here we can use the work energy theorem

here we know that

as it come to rest finally



now work done by friction force will be given as


Work done by spring force is given as



so now plug in all data above


so above is the friction coefficient
When hockey players push the puck along the ice it slides causing heat which melts the ice causing the friction against the ice to be less.
Let
be the height of the building and thus the initial height of the ball. The ball's altitude at time
is given by

where
is the acceleration due to gravity.
The ball reaches the ground when
after
. Solve for
:


so the building is about 16 m tall (keeping track of significant digits).