Atoms are added to crystal faces.
Answer:
The new self inductance is 3 times of the initial self inductance.
Explanation:
The self inductance of a solenoid is given by :

Where
N is number of turns per unit length
A is area of cross section
l is length of solenoid
If length and number of coil turns are both tripled,
l' = 3l and N' = 3N
New self inductance is given by :

So, the new self inductance is 3 times of the initial self inductance.
I would say D would be the answer. but is this even a real like homework question
Answer:
437.5Kjoules
Explanation:
K.E=half multiply by mass multiply by square of velocity
=437.5Kjoules