Question

4. cm A toroid of inner and outer radius 10 cm and 20 respectively and number of turns 100 carries a current of 2 A. The magnetic field at the centre 'O' is (1) 2.67 x 10-4 T (2) 2.53 x 10-4 T (3) 2.84 x 10-4 T *(4) Zero​

Answer 1

Answer:

4. cm A toroid of inner and outer radius 10 cm and 20 respectively and number of turns 100 carries a current of 2 A. The magnetic field at the centre 'O' is (1) 2.67 x 10-4 T (2) 2.53 x 10-4 T (3) 2.84 x 10-4 T *(4) Zero

Answer 2

Given:

N=100

Ri =10cm=0.10m

Ro=20cm=0.20m

R=Ri + Ro/2

  =0.10+0.20/2=0.15

I=2A

μ0 =4π×10−7TmA  −1

The magnetic field inside the toroid will be

B=μ0NI/2πR

 =4π×10−7×100×2/2π×0.15

=2.67×10-4T

The correct option is "a"

The answer is 2.67×10-4T

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