COMEDK2012PhysicsElectromagnetic Induction
The current in a coil changes from 1 ~mA to 5 ~mA in 4 milli secon(d) If the coefficient of self-induction of the coil is 10 mH , then the magnitude of the self-induced emf is
Options
- A10 mV
- B5 mV
- C2.5 mV
- D1 mV
Correct answer
A. 10 mV
Step-by-step solution
Given, I₁=1 ~mA =1 10⁻³ ~A I₂=5 ~mA =5 10⁻³ ~A t=4 ~ms =4 10⁻³ ~s L=10 ~m H =10 10⁻³ H Self-induced emf, |e|=L d I d t =10 10⁻³ (5-1) 10⁻³ 4 10⁻³ =10 mV