NTA Abhyas JEE Main2020PhysicsMagnetic Properties of MatterPractice
A vibration magnetometer consists of two identical bar magnets placed one over the other such that they are mutually perpendicular and bisect each other. The time period of the combination is 4 s . If one of the magnets is removed, then the time period of other one will be
Options
- A5.78   s
- B3.36   s
- C4.36   s
- D5.36   s
Correct answer
B. 3.36   s
Step-by-step solution
As magnets are perpendicular to each other, the resultant magnetic moment M ' = M 2 + M 2 = 2 M ∴ T 1 = 2 π 2 I 2 M H In the second case, T 2 = 2 π I MH T 2 T 1 = 1 2 1 / 4 ∴ T 2 = 4 2 1 / 4 = 3.36 s