A compass needle of magneticmoment60 Am^(2)pointing geopgraphical north at a place where the horizontal componentof earth fiedlis 40 mu Wbm^(-2)experiences a torque of 1.2 xx10^(-3) Nmthe declination of the place is

A compass needle of magneticmoment60 Am^(2)pointing geopgraphical nort

1.	A compass needle of magneticmoment60 Am^(2)pointing geopgraphical north at a place where the horizontal componentof earth fiedlis 40 mu Wbm^(-2)experiences a torque of 1.2 xx10^(-3) Nmthe declination of the place is
Answer» `15^(@)` `30^(@)` `45^(@)` `60^(@)` Solution :`tau =MH sin theta` `THEREFORE sin theta =(tau)/(MH)=1/2 therefore theta =30^(@)`

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A compass needle of magneticmoment60 Am^(2)pointing geopgraphical north at a place where the horizontal componentof earth fiedlis 40 mu Wbm^(-2)experiences a torque of 1.2 xx10^(-3) Nmthe declination of the place is

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