Other / Mixed

An electron (mass $m$) is accelerated through a potential difference of '$V$' and then it enters in a magnetic field of induction '$B$' normal to the lines. The radius of the circular path is ($e =$ electronic charge)

Given below are two statements:

Statement I: If the number of turns in the coil of a moving coil galvanometer is doubled then the current sensitivity becomes double.

Statement II: Increasing current sensitivity of a moving coil galvanometer by only increasing the number of turns in the coil will also increase its voltage sensitivity in the same ratio In the light of the above statements, choose the correct answer from the options given below:

Two coaxial solenoids of different radius carry current $I$ in the same direction. $\vec{F_1}$ be the magnetic force on the inner solenoid due to the outer one and $\vec{F_2}$ be the magnetic force on the outer solenoid due to the inner one. Then: