NTA Abhyas JEE Main2020PhysicsElectromagnetic InductionPractice
In a magnetic field of 0.05 T , area of a coil changes from 101 cm 2 to 100 cm 2 without changing the resistance which is 2 Ω . The amount of charge that flows during this period is
Options
- A2 · 5 × 10 − 6 C
- B2 × 10 − 6 C
- C10 − 6 C
- D8 × 10 − 6 C
Correct answer
A. 2 · 5 × 10 − 6 C
Step-by-step solution
B = 0.05   T A 1 = 101     cm 2 = 101 × 10 − 4     m 2 A 2 = 100     cm 2 = 100 × 10 − 4     m 2 R = 2    Ω Amount of charge flown is given by, q = B ( Δ   A ) R = 0.05 × 1 0 1 × 1 0 - 4 - 1 0 0 × 1 0 - 4 2 = 0.05 × 1 × 1 0 - 4 2 = 2.5 × 1 0 - 6   C