Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE MainPhysicsAlternating Current

An alternating voltage given by V = 200 2 (100 t) V is applied across a pure capacitor. If the measured RMS current in the circuit is 2 A, the capacitance of the capacitor is:

Options

  1. A50 2 F
  2. B100 F
  3. C100 F
  4. D100 2 F

Correct answer

C. 100 F

Step-by-step solution

The given voltage equation is V = 200 2 (100 t) V. Comparing this with the standard equation V = V_m ( t) , we get: Peak voltage, V_m = 200 2 V Angular frequency, = 100 rad/s The RMS voltage is given by: V_ rms = V_m 2 = 200 2 2 = 200 V The RMS current in a purely capacitive circuit is: I_ rms = V_ rms X_C = V_ rms C Substituting the given values ( I_ rms = 2 A): 2 = 200 100 C C = 2 20000 = 10⁻⁴ F Converting to microfarads: C = 10⁻⁴ 10^6 F = 100 F Answer: 100 F

Practice Alternating Current on Quantrex Academy →

More from Alternating Current

Consider a circuit consisting of a capacitor of capacitance C and a coil with N turns per unit length, cross sectional area S and length d , where d^2 S . There is another coil of 2026An LCR series circuit driven with E_ rms = 90 V at frequency f_d = 30 Hz has resistance R = 80 , , an inductance with inductive reactance X_L = 20.0 , and capacitance with capacitiv 2026A series LCR circuit with R = 20 , L = 1.6 H and C = 40 F is connected to a variable frequency a.c. source. The inductive reactance at resonant frequency is _______ . 2026An a.c. source of angular frequency is connected across a resistor R and a capacitor C in series. The current is observed as I . Now the frequency of the source is changed to /4 , 2026An inductor of 10 mH, capacitor of 0.1 F and a resistor of 100 are connected in series across an a.c power supply 220 V, 70 Hz. The power factor of the given circuit is 0.5 . The d 2026The figure given below shows an LCR series circuit with two switches S₁ and S₂ . When switch S₁ is closed keeping S₂ open, the phase difference ( ) between the current and source v 2026An inductor stores 16 J of magnetic field energy and dissipates 32 W of thermal energy due to its resistance when an a.c. current of 2 A (rms) and frequency 50 Hz flows through it. 2026The electric current in the circuit is given as i=i_ o (t / T) . The r.m.s current for the period t=0 to t=T is _ _ _ _ . 2026 Full Alternating Current list All JEE Main PYQs