A toroid wound with 100 turns /m of wire carries a current of 3 A. The core of toroid is made of iron having relative magnetic permeability of `mu_(r)= 5000 mu_(0)` under given conditions. The magnetic field inside the iron is …........
(Tackle `mu_0 = 4pi xx 10^(-7) T mA^(-1) )`

Options

A. 0.15 T
B. 0.47 T
C. `1.5 xx 10^(-2) T`
D. `1.88 T`

Answer

D

Explanation

Here `mu_(r) = 5000 mu_(0) `
`= 5000 xx 4pi xx 10^(-7)`
`H=i_(f) = nI_(f)`
`B= mu_(r) H" "H= 100 xx 3 = 300 "Am"^(-1)`
`= 5000 xx 4 xx 3.14 xx 10^(-7) xx 300`
`= 60 xx 3.14 xx 10^(-2) = 188.4 xx 10^(-2)`
`therefore B ~~ 1.88 T`