Physics-Motional EMF

NEET Physics Motional EMF MCQ Question

Type: MCQ-numerical-Easy-Class 12

A horizontal straight wire 10 m long is falling with a speed of 5.0 m/s at right angles to the horizontal component of the Earth's magnetic field, 0.30 × 10⁻⁴ Wb/m². What is the instantaneous value of the emf induced in the wire?

A

0.15 V

B

1.5 V

C

0.03 V

D

3.0 V

Correct Answer

Option A

Detailed Explanation

The induced emf (ε) is calculated using the formula ε = Bvl, where B is the magnetic field (0.30 × 10⁻⁴ T), v is the velocity (5.0 m/s), and l is the length of the wire (10 m). Thus, ε = 0.30 × 10⁻⁴ × 5.0 × 10 = 0.15 V.

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