Pumice is used for cleaning foot. Foot are wet with warm water and then scrub by pumice so that hard and dry skin can be removed. It is quite effective in cleaning skin.
Pumice is also used as light weight material in concrete mix. Due to it porous texture, it is a good light weight material.
Answer: 600N
Explanation:
Centripetal force is the force that causes a body to move in a circular path.
Centripetal force = MV²/r
M = 75kg v = 80m/s r = 0.80km = 800m
Substituting the values given in the formula;
F = 75 × 80²/800
F = 600N
The magnitude of the resultant force on the 75kg pilot is 600N.
In the middle the nucleus is thr brain of it and the electrons spin around the whole atom
Explanation:
In the given situation two forces are working. These are:
1) Electric force (acting in the downward direction) = qE
2) weight (acting in the downward direction) = mg
Therefore, work done by all the forces = change in kinetic energy
Hence,
It is known that the weight of electron is far less compared to electric force. Therefore, we can neglect the weight and the above equation will be as follows.

v = 
= 592999 m/s
Since, the electron is travelling downwards it means that it looses the potential energy.