A closely wound solenoid of 1000 turns and area of cross section `1.4xx10^(-4)m^(2)` carrying a current of 3 A is suspended through its centre allowing it to turn in a horizontal plane. The magnetic moment associated with this solenoid is

Options

A. `0.22JT^(-1)`
B. `0.32JT^(-1)`
C. `0.42JT^(-1)`
D. `0.52JT^(-1)`

Answer

C

Explanation

Here, n=1000, A=`1.4xx10^(4)m^(2), I=3A`
`m=nIA=1000xx3xx1.4xx10^(-4)=0.42JT^(-1)`