Answer:

Explanation:
The electrostatic attraction between the nucleus and the electron is given by:
(1)
where
k is the Coulomb's constant
Ze is the charge of the nucleus
e is the charge of the electron
r is the distance between the electron and the nucleus
This electrostatic attraction provides the centripetal force that keeps the electron in circular motion, which is given by:
(2)
where
m is the mass of the electron
v is the speed of the electron
Combining the two equations (1) and (2), we find

And solving for v, we find an expression for the speed of the electron:

Elevation would be showing you what height you are at, energy would be like what force your putting into the object.
Answer:
You are given that the mass of the clock M is 95 kg.
This is true whether the clock is in motion or not.
Fs is the frictional force required to keep the clock from moving.
Thus Fk = uk W = uk M g the force required to move clock at constant speed. (the kinetic frictional force)
uk = 560 N / 931 N = .644 since the weight of the clock is 931 N (95 * 9.8)
us is the frictional force requited to start the clock moving
us = static frictional force = 650 / 931 -= .698