A solenoid of length 1.0 m has a radius of 1 cm and has a total of 1000 turns wound on it. It carries a current of 5A. If an electron was to move with a speed of `10^(4) ms^(-1)` along the axis of this current carrying solenoid, then force experienced by this electron is

Options

A. 2N
B. 1.2 N
C. zero
D. 2.5 N

Answer

c

Explanation

Here, L=1m , N=1000
The number of turns per unit length
n=N/L =1000 turn/m
Magnetic field inside the solenoid
`B=mu_(0)nI=mu_(0)xx1000xx5=2pixx 10^(-3) T`
The direction of magnetic field is along the solenoid. For electron , `q=-e, v =10^(4) ms^(-1)`
Magnetic Lorentz force, `F=evB sin 0^(@) =0` as the angle between B and v is `0^(@)`