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 aluminium, the magnetic field is `B_(0) = μ_(0)H` .As the space inside the toroid is filled with aluminium, the field becomes `B=mu_(H)=mu_(0)(1+chi)H`
The percent increases is `(B-B_(0))/(B_(0))xx100=(mu_(0)chiH)/(mu_(0)H)xx100`
`=chixx100=2.1xx10^(-3)`