A circular loop of 2 turns carries a current of `5*0A`. If the magnetic field at the centre of loop is `0*40mT`, find the radius of the loop.

Answer

1.57

Explanation

Here, n = 2,I = 5.0A,
`B=0.4xx10^(-3)T,r = ?`
Magnetic field at the centre of current loop is
`B= (mu_0)/(4pi)(2pi nI)/r ` or `r =(mu_0)/(4pi)(2pinI)/B`
`:. r =10^(-7)xx 2 xx22/7 xx(2xx5.0)/(0.4 xx10^(-3))`
`=1571.xx10^(-4) m = 1.57 cm`