Two bar magnets of the same mass, same length and breadth but having magnetic moments M and 3M are joined together pole for pole and suspended by a string. The time period of assembly in a magnetic field of strength 1 H is 3 s . If now the polarity of one of the magnets is reversed and the combination is again made to oscillate in the same field, the time of oscillation is

Question

Two bar magnets of the same mass, same length and breadth but having magnetic moments M and 3M are joined together pole for pole and suspended by a string. The time period of assembly in a magnetic field of strength 1 H is 3 s . If now the polarity of one of the magnets is reversed and the combination is again made to oscillate in the same field, the time of oscillation is (A) 3 texts (B) 3√3 s (C) 3/√3 text s (D) 3√2 texts

Tardigrade Admin · Accepted Answer

In pole for pole combination, M1=3M+M= 4M and if the polarity is reversed textitM2=3 textitM- textitM=2 textitM textitT2=? ( textitT2/ textitT1)=√(M1/M2)=√(4 M/2 M) textitT2=√2 textitT1=3√2 texts

$3 s$

$33$ $s$

$3/ 3 s$

$32 s$

In pole for pole combination,
$M_{1} = 3 M + M = 4 M$
and if the polarity is reversed $M_{2} = 3 M - M = 2 M$
$T_{2} = ?$
$\frac{T _{2}}{T _{1}} = \frac{M _{1}}{M _{2}} = \frac{4 M}{2 M}$
$T_{2} = 2 T_{1} = 32 s$

3s

33​ s

3/3​ s

32​s

In pole for pole combination, M1​=3M+M=4M and if the polarity is reversed M2​=3M−M=2M T2​=? T1​T2​​=M2​M1​​​=2M4M​​ T2​=2​T1​=32​s

$3 s$

$33$ $s$

$3/ 3 s$

$32 s$

In pole for pole combination,
$M_{1} = 3 M + M = 4 M$
and if the polarity is reversed $M_{2} = 3 M - M = 2 M$
$T_{2} = ?$
$\frac{T _{2}}{T _{1}} = \frac{M _{1}}{M _{2}} = \frac{4 M}{2 M}$
$T_{2} = 2 T_{1} = 32 s$