JEE Main201912 Jan 2019Evening ShiftPhysicsElectromagnetic InductionActual
A 10 m long horizontal wire extends from North East to South West. It is falling with a speed of 5.0 m s - 1 , at right angles to the horizontal component of the earth's magnetic field of 0.3 × 10 - 4 Wb m - 2 . The value of the induced emf in the wire is:
Options
- A0.3 × 10 - 3   V
- B1.1 × 10 - 3   V
- C2.5 × 10 - 3   V
- D1.5 × 10 - 3   V
Correct answer
B. 1.1 × 10 - 3   V
Step-by-step solution
The wire makes an angle 45 ° with the magnetic field lines. Therefore, the induced emf will be, ε = B v l sin 45 0 = 0.3 × 10 - 4 × 5 × 10 × 1 2 = 1.1 × 10 - 3   V