Solution :
a). Using Gauss's law :
,
.........(1)
Let
in equation (1)
Therefore,
.............(2)



....................(3)
Therefore, 

.............(4)
Now differentiating the equation (4) w.r.t. 'b', we get
Thus the radius for the inner cylinder conductor is 
b). For the energy storage, substitute the radius in (4), we get

This is the amount of energy stored in the conductor.
Answer:
These molecules push the layer of molecules down / near, so they also start to vibrate. In this way, the oscillation is followed by one molecule next to it.
Answer:
h≅ 58 m
Explanation:
GIVEN:
mass of rocket M= 62,000 kg
fuel consumption rate = 150 kg/s
velocity of exhaust gases v= 6000 m/s
Now thrust = rate of fuel consumption×velocity of exhaust gases
=6000 × 150 = 900000 N
now to need calculate time t = amount of fuel consumed÷ rate
= 744/150= 4.96 sec
applying newton's law
M×a= thrust - Mg
62000 a=900000- 62000×9.8
acceleration a= 4.71 m/s^2
its height after 744 kg of its total fuel load has been consumed


h= 58.012 m
h≅ 58 m
There are two equal forces of gravity between the Earth and the Moon.
One force pulls the Moon toward the Earth.
The other force pulls the Earth toward the Moon.
If only this gravity suddenly switched off, then the moon would
continue to orbit the Sun, very much as it does now.
If ALL gravity suddenly switched off, then . . .
-- the Moon would stop orbiting the Earth and would sail away, in
a straight line and at the speed it had when gravity disappeared;
-- the Earth would stop orbiting the Sun and would sail away, in
a straight line and at the speed it had when gravity disappeared;
-- all the gases surrounding the Earth ... which we call "air" ... would
start drifting away, and expanding into a giant cloud of gas, and stop
being an atmosphere;
-- the Sun would completely fall apart, expand into a giant cloud of gas,
and stop being a star.