Home
Class 12
PHYSICS
An AC voltage source of variable angular...

An AC voltage source of variable angular frequency `(omega)` and fixed amplitude `V_(0)` is connected in series with a capacitance C and an electric bulb of resistance R (inductance zero). When `(omega)` is increased

A

The bulb glows dimmer

B

The bulb glows brighter

C

Total impedence of the circuit is unchanged

D

Total impendance of the circuit increases

Text Solution

Verified by Experts

The correct Answer is:
B
Impendance `Z=[R^(2)+1/((omegaC)^(2))]^(1//2), I_(0)=V/Z` As `omega` increases, `Z` decreases. Hence the current `I_(0)` increass. Therefore, the blub glows brighter, which is choice `(B)`.
Promotional Banner

Similar Questions

Explore conceptually related problems

The power factor of an AC circuit having resistance (R) and inductance (L) connected in series and an angular velocity omega is

A box P and a coil Q are connected in series with an AC source of variable frequency. The emf of the source is constant at 10 V . Box P contains a capacitance of 1 mu F in series with a resistance of 32 Omega . Coil Q has a self-inductance 4.9 mH and a resistance of 68 Omega in series. The frequency is adjusted to that the maximum current flows in P and Q . At this frequency (a) The impedance of P is 77 Omega (b) The impedance of Q is 85 Omega (c ) Voltage across P is 7.7 V (d) Voltage across Q is 9.7 V

A series LCR circuit having resistance R, capacitance C and inductance L has a voltage source of angular frequency omega and voltage V_(in). Output voltage (V_(out)) is taken as voltage across the resistor and inductor combined. (a) Find eta=(V_(out))/V_("in") (b) Find eta in the limit of large omega(omegagtgt(1)/(RC),(1)/(sqrt(LC)),(R)/(L)) (C )Find eta in the limit of small omega(omegagtgt(1)/(RC),(1)/(sqrt(LC)),(R)/(L))

A box P and a coil Q are connected in series with an AC source of variable frequency.The EMF of source is constant at 10 V .Box P contains a capacitance of 1 muF in series with a resistance of 32 Omega .Coil Q has a self inductance 4.9 mH and a resistance of 68 Omega .The frequency is adjusted so that the maximum current flows in P and Q .Find the impedance of P and Q at this frequency.Also find the voltage across P and Q respectively.