Question

A 0.50-m long solenoid consists of 1 000 turns of copper wire wound with a 4.0 cm radius. When the current in the solenoid is 18 A, the magnetic field at a point 1.0 cm from the central axis of the solenoid is____.

a) 0.090 mT. b) 0.36 mT. c) 23 mT. d) 36 mT. e) 45 mT.

Answer 1

option E

Step-by-step explanation:

Given,

Length of the solenoid = 0.50 m

Number of turn = 1000 turn

radius, r = 4 cm

Current = 18 A

Magnetic field inside the solenoid.

`B = \mu_0 NI`

`B = \mu_0 ((N)/(L))I`

`B = 4\pi * 10^(-7)* ((1000)/(0.5))* 18`

`B = 0.045\ T`

`B = 45\ mT`

Hence, the correct answer is option E