JEE Main 2019 Physics question
A 10 m long horizontal wire extends from North East to South West. It is falling with a speed of 5.0 ms, at right angles to the horizontal component of the earth's magnetic field of Wb/m. The value of the induced emf in wire is:
Answer: (D)
Solution
Effective length perpendicular to is 10 sin 45°: emf = 0.3 × 10 × 5 × 7.07 ≈ 1.1 × 10 V.