A certain superconducting magnet in the form of a solenoid of length 0.26 m can generate a magnetic field of 7.5 T in its core when its coils carry a current of 80 A. The windings, made of a niobium-titanium alloy, must be cooled to 4.2 K. Find the number of turns in the solenoid.

Therefore

Number of turns in the solenoid is 19407.

Explanation:

Given:

Strength magnetic field at its center,

B = 7.5 T

length of solenoid = l = 0.26 m

Current, I = 80 A

To Find:

Turn = N = ?

Solution:

If N is the number of turns in the length, the total current through the rectangle is NI. Therefore, Ampere’s law applied to this path gives

Therefore,

Where,  

B = Strength of magnetic field

l = Length of solenoid

N = Number of turns

I = Current

Substituting the values we get

Therefore

Number of turns in the solenoid is 19407.

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