Question

Solenoid of length 10 cm and radius 1 cm contains 200 turns and carries a current of 10 ampere the value of pole strength of each pole is

Answer 1

Answer: $M = 2\pi Am$

Explanation: The pole strength is the product of number of turns per unit length , area and current.

Given that,

Length l = 0.1 m

Radius r = 0.01 m

Number of turns per unit length $n = \dfrac{N}{l} = \dfrac{200}{0.1}$

Current in the solenoid i = 10 A

The pole strength is

M = nIA

$M = \dfrac{200}{0.1}\times10 A\times \pi\times 0.01m\times0.01m$

$M = 2\pi Am$

Hence, the pole strength is $M = 2\pi Am$.

Answer 2

"Formula:

M = n I A

Where, M = pole strength

            $n = \frac {N} {l}$ is the number of turns per unit length.

Given that,

Length l = 0.1 m

Radius r = 0.01 m

Number of turns per unit length   $n = \frac {N} {l} =\frac { 200 }{ 0.1 }$

Current in the solenoid I = 10 A

The pole strength is

M = n I A

$M = \frac {200} {0.1} \times 10 \times \pi \times 0.01 \times 0.01$

$M = 2 \pi Am$"