Answer:
Lubrication is used to reduce friction. It is generally used for moving machine parts. The lubricants are the substances which are used to reduce the friction which acts between two surfaces in contact, between which relative motion can occur.
Answer:
The current of the outer coil is 
Explanation:
From the question we are told that
The number of turns of the inner coil is 
The radius of the inner coil is
The current of the inner coil is 
The number of turns of the outer coil is 
The radius of the outer coil is 
Generally the net magnetic field is mathematically represented as

Now from told that the net magnetic field is common
So

Here
is the permeability of free space
making
the subject

substituting values


Relative to the floor it's resting on, its height is zero,
so its potential energy is zero.
Relative to the next floor down, its height could be
three or four meters, and it could have plenty of
potential energy ... if you cut out a circle in the floor
all around the rock, and let it fall to next floor down,
it could really do some damage. Look out below ! !
<span>Option C, are those that have the same number of protons in the nucleus. The atoms isotopes are atom that belongs to the same element, they are inside the periodic table and its nucleus has a different quantity of neutrons.</span>