By Team Aakash Byju's | 2nd December 2022

A tangent galvanometer has a coil of 50 turns and a radius of 20 cm. The horizontal component of the earth's field is 3×10 T. Find the current through the coil.

0.5 A

0.39 A

0.29 A

0.19 A

A.

B.

C.

D.

-5

Detailed Explanation

We are asked to find the current through the coil in a tangent galvanometer due to which there is a deflection of 45.

0

Given,

B = 3×10

H

-5

T

,

n = 50 turns,

r = 20 cm = 20×10 m.

-2

The formula to be used is:

I =

2rB tanθ

H

µ n

0

Let us consider the deflection is 45° so that tan θ = tan 45° = 1.

=> I =

2 × 20 × 10

-2

× 3 × 10

-5

50 × 4π × 10

-7

(∵ µ =4π × 10 )

-7

=> I =

0.19 A

(∵ π =

22

7

)

0