NEET2019PhysicsElectromagnetic InductionActual
A 800 turn coil of the effective area 0.05    m 2 is kept perpendicular to the magnetic field 5 × 10 - 5    T . When the plane of the coil is rotated by 90 o around any of its coplanar axis in 0.1   s , the emf induced in the coil will be:
Options
- A2 V
- B0.2 V
- C2 × 10 - 3 V
- D0.02 V
Correct answer
D. 0.02 V
Step-by-step solution
By Faraday's law, induced EMF in coil is equal to rate of change of magnetic flux linked with coil so ε = - ∆ ϕ ∆ t = - ϕ f - ϕ i ∆ t = - 0 - N B A ∆ t = 800 × 5 × 10 - 5 × 0.05 0.1 = 0.02   V