COMEDK2014PhysicsAlternating Current
A sinusoidal voltage of peak value 300 ~V and an angular frequency =400 rads ⁻¹ is applied to series L-C-R circuit, in which R=3 , L=20 mH and C=625 F . The peak current in the circuit is
Options
- A30 2 ~A
- B60 ~A
- C100 ~A
- D60 2 ~A
Correct answer
B. 60 ~A
Step-by-step solution
Given, V_ m =300 ~V , =400 rads ⁻¹ R=3 , L=20 mH =20 10⁻³ H and C=625 F =625 10⁻⁶ ~F Impedance of the circuit, Z= R²+ (X_ L -X_ C )² Here, X_ L = L=400 20 10⁻³=8 and X_ C = 1 C = 1 400 625 10⁻⁶ =4 Z= 3²+(8-4)² = 25 =5 Peak current, I_ m = V_ m Z = 300 5 =60 ~A