The area of hysteresis loop of a material is equinalent to 250 joule. When 10 kg material is magnetised by an alternating field of 50 Hz then energy lost in one hour will be if the density of material is `7.5 gm//cm^(2)`

Options

A. `6 xx 10^(4) J`
B. `6 xx 10^(4)` erg
C. `3 xx 10^(2) J`
D. `3 xx 10^(2)` erg

Answer

A

Explanation

Energy `= nA V t = nA (m)/(d) t= (50 xx 250 xx 10 xx 3600)/(7.5 xx 10^(3))`
`= 6 xx 10^(4) J`