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The combination of two bar magnets makes...

The combination of two bar magnets makes 10 oscillations per second in an oscillation magnetometer when like poles are tied together and 2 oscillations per second when unlike poles are tied together. Find the ratio of the magnetic moments of the magnets. Neglect any induced magnetism.

Text Solution

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WE know `u = (1)/(2 pi) sqrt((mB_(H))/(1))`
For like poles tied togather
`M = M_(1) - M_(2)`
For unlike pole
` M = M_(1) + M_(2) `
`v_(1))/(v_(2)) = sqrt(M_(1) - M_(2))/(M_(1) + M_(2)))`
` rArr ((10)/(1))^(2) = (M_(1) - M_(2))/(M_(1) + M_(2))`
` rArr (25)/(1) = (M_(1) - M_(2))/(M_(1) + M_(2))`
`rArr (25 + 1)/(25 - 1) = (M_(1) - M_(2) + M_(1) + M_(2))/(M_(1) - M_(2) - M_(1) - M_(2))`
rArr (26)/(24) = (2M_(1))/(-2M_(2))`
`rArr (M_(1))/(M_(2)) = - (26)/(24) = - (13)/(12) `
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HC VERMA-PERMANENT MAGNETS-Exercise
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  5. A magnetic dipole of magnetic moment 0.72(sqrt(2) Am^2) is placed hori...

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  7. If the earth's magnetic field has a magnitude 3.4 xx 10^(-5) T at the ...

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  10. The needle of a dip circle shows an apparent dip of 45^@ in a particul...

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  13. A short magnet produces a deflection of 37^@ in a deflection magnetome...

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  15. A deflection megnetometer is placed with its arms in north-south direc...

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  16. A bar magnet takes pi/10 second to complete one oscillation in an osci...

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  17. The combination of two bar magnets makes 10 oscillations per second in...

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  18. A short magnet oscillates in a vibration magnetometer with a time per...

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  19. A bar magnet makes 40 oscillations per minute in an oscillation magnet...

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