Time period of any magnetic body place in an external magnetic field is:-
T=2πMBI
Thoop=2πMBmR2 ...... (1) Ihoop=mR2
Tc=2π2M(B)2mR2 ...... (2) ISolidcylinder=2mR2
From (1) and (2)
Th=Tc
A hoop and a solid cylinder of same mass and radius are made of a permanent magnetic material with their respective axes. But the magnetic moment of…
JEE Main 2019 — Physics Waves & Oscillations
2019mcqeasy
A hoop and a solid cylinder of same mass and radius are made of a permanent magnetic material with their respective axes. But the magnetic moment of hoop is twice of solid cylinder. They are placed in a uniform magnetic field in such a manner that their magnetic moments make a small angle with the field. If the oscillation periods of hoop and cylinder are Th and Tc respectively, then:
Official previous-year question
Held on 10 Jan 2019 · Verified 6 Jul 2026.
Options
- A
Th=2Tc
- B
Th=Tc
- C
Th=0.5Tc
- D
Th=1.5Tc
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