Force between two identical bar magnets whose centres are r metre apart is `4.8 N`, when their axes are in the same line. If separation is increased to `2r`, the force between them is reduced toA. `2.4 N`B. `1.2 N`C. `0.6 N`D. `0.3 N`

Force between two identical bar magnets whose centres are r metre apar

1.	Force between two identical bar magnets whose centres are r metre apart is `4.8 N`, when their axes are in the same line. If separation is increased to `2r`, the force between them is reduced toA. `2.4 N`B. `1.2 N`C. `0.6 N`D. `0.3 N`
Answer» Correct Answer - D In magnetic dipole, force `prop1/r^(4)` Hence, new force `=4.8/2^(4)=4.8/16=0.3 N`

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Force between two identical bar magnets whose centres are r metre apart is `4.8 N`, when their axes are in the same line. If separation is increased to `2r`, the force between them is reduced toA. `2.4 N`B. `1.2 N`C. `0.6 N`D. `0.3 N`

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