The bicycle is on top of the hill, so its potential energy is Gravitational potential energy.
Gravitational potential energy = mass × height × acceleration due to gravity
G.P.E = mgh
= 25 × 9.81 × 3
= 735.75 J
Hope it helped!
The work done by the battery to charge the capacitor is equal to the electric potential energy stored in the capacitor at full charge, which is given by:
where
is the capacitance of the capacitor
is the voltage across the capacitor (which corresponds to the voltage of the battery)
By substituting the numbers into the equation, we find the work done:
Translate it to English for me to better understand