Question

a long solenoid of diameter 0.1 m has 2 * 10^4 turns per meter at center of solenoid a coil of 100 turns and radius 0.01 m is placed

Answer 1

We have two relationships here :

The solenoid and the coil which is put at the center of the solenoid.

THEIR CIRCUMFERENCES

The solenoid's circumference is 10 times larger than the coil's circumference.

CALCULATIONS : 0.1 /0.01 = 10

The length of the coil is :

3.142 × 0.01 × 2 × 100 = 6.284m

The length of the solenoid is :

10 × 6.284 m = 62.84m

The number of turns the solenoid can make on the coil are :

1 meter = 2 × 10⁴

62.84m =?

62.84 × 20000 = 1256800 turns.

1.2568 × 10⁶ turns.