Find the percent increase in the magnetic field `B` when the space within a current- carrying toroid is filled with aluminium. The susceptibility of aluminium is `2.1 xx 10^(-5)`.

Explanation

In absence of Al , `B_(0) = mu_(0) H`
In presence of Al , B = `mu H`
`B = mu_(0) [1 + chi ] H`
Percentage increase in B
`(B- B_(0))/(B_(0)) xx 100 = (mu_(0) chi H)/(mu_(0)H) xx 100`
`= chi xx 100 `
`= 2.1 xx 10^(-5) xx 100`
`= 2.1 xx 10^(-3)`