Verified Solution • 2025–26 Session
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QJEEM23Phf5c4: JEE Main 2023 Physics - Class 12 JEEM23Phf5c4 Solution: A straight wire of mass and length is suspended by a pair of…
A straight wire of mass and length is suspended by a pair of flexible leads in uniform magnetic field of magnitude as shown in the figure. The magnitude of the current required in the wire to remove the tension in the supporting leads is ___________ A.
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Step-by-Step Verified Solution
In the given situation, the wire is suspended by a pair of flexible leads in a uniform magnetic field. Due to the magnetic field, the wire experiences a magnetic force which causes it to hang at an angle to the vertical. The tension in the flexible leads provides the restoring force to balance the weight of the wire.
For equilibrium, the magnetic force on the wire should balance the weight of the wire. Therefore, we can write:
where is the magnetic force on the wire, is the acceleration due to gravity, is the current flowing through the wire, is the length of the wire, and is the magnitude of the magnetic field.
Solving for , we get:
Substituting the given values, we get:
Therefore, the magnitude of the current required in the wire to remove the tension in the supporting leads is 2 A.
For equilibrium, the magnetic force on the wire should balance the weight of the wire. Therefore, we can write:
where is the magnetic force on the wire, is the acceleration due to gravity, is the current flowing through the wire, is the length of the wire, and is the magnitude of the magnetic field.
Solving for , we get:
Substituting the given values, we get:
Therefore, the magnitude of the current required in the wire to remove the tension in the supporting leads is 2 A.