Answer:
Current in outer circle will be 15.826 A
Explanation:
We have given number of turns in inner coil 
Radius of inner circle 
Current in the inner circle 
Number of turns in outer circle 
Radius of outer circle 
We have to find the current in outer circle so that net magnetic field will zero
For net magnetic field current must be in opposite direction as in inner circle
We know that magnetic field is given due to circular coil is given by

For net magnetic field zero

So 

Answer:
Explanation:
Potential energy on the surface of the earth
= - GMm/ R
Potential at height h
= - GMm/ (R+h)
Potential difference
= GMm/ R - GMm/ (R+h)
= GMm ( 1/R - 1/ R+h )
= GMmh / R (R +h)
This will be the energy needed to launch an object from the surface of Earth to a height h above the surface.
Extra energy is needed to get the same object into orbit at height h
= Kinetic energy of the orbiting object at height h
= 1/2 x potential energy at height h
= 1/2 x GMm / ( R + h)
In the blank should go of friction.
Answer;
=32.15 meters
Explanation;
Use the formula
s= ut+ 0.5 a (t)^2 to find out 's'
where s= distance traveled
u=initial velocity which is zero in this case
t= time taken to travel 's' distance
a=acceleration (due to gravity on moon i.e 1.62 m/s^2 )
Therefore;
S = 0.5 * 1.62 * 6.3 * 6.3
= 32.1489 meters
Thus; the crater is 32.15 meters deep.