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 increase.

A

the bulb glows dimmer

B

the bulb glows brighter.

C

total impedance of the circuit is unchanged

D

total impedance of the circuit increase.

Text Solution

Verified by Experts

The correct Answer is:
B
(b) When capacitor is connected in series with the resistor then impedance of the circuit is given by the following relation :
`Z = sqrt(R^(2)+(1)/(omega^(2)C^(2)))`
Hence when angular frequency is increased then impedance of the circuit is decreased. Due to decrease in imedance current flowing in the circuit increases and hence bulb glows brighter. Option ( b) corrcet.
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • ALTERNATING CURRENT

    MODERN PUBLICATION|Exercise COMPETITION FILE C. MULTIPLE CHOICE QUESTIONS|17 Videos

  • ALTERNATING CURRENT

    MODERN PUBLICATION|Exercise COMPETITION FILE D. MULTIPLE CHOICE QUESTIONS|13 Videos

  • ALTERNATING CURRENT

    MODERN PUBLICATION|Exercise COMPETITION FILE JEE (MAIN) & OTHER STATE BOARDS FOR|26 Videos

  • ATOMS

    MODERN PUBLICATION|Exercise Chapter Practice Test|16 Videos

Similar Questions

Explore conceptually related problems

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.

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))

Knowledge Check

  • An a.c. voltage source of variable angular frequency w and fixed amplitude V, is connected in series with a capacitance C and an electric bulb of resistance R (inductance zero). When a is increased.

    A
    the bulb glows dimmer.
    B
    the bulb glows brighter.
    C
    total impedance of the circuit is unchanged.
    D
    total impedance of the circuit increases.

  • An alternating voltage source of variable angular frequency 'o' and fixed amplitude V is connected in series with a capacitance C and electric bulb of resistance R (inductance zero). When ' omega ' is increased:

    A
    The bulb glows dimme
    B
    The bulb glows brighter
    C
    Net impedance of the circuit remains unchanged
    D
    Total impedance of the circuit increases

  • A lamp of 6 V, 12 W is connected in series with a resistance R and an electrical source of 12 V. To light the bulb property, value of R should be

    A
    `2Omega`
    B
    `6Omega`
    C
    `3Omega`
    D
    None of the above

    • Similar Questions

    Explore conceptually related problems

    A lamp of 6 V, 12 W is connected in series with a resistance R and an electrical source of 12 V. To light the bulb property, value of R should be

    An alternating voltage, of angular frequency omega is induced in electric circuit consistin of inductance L and capacitance C, connected in parallel. Then across the inductance coil

    An a.c. source of variable angular frequency o is connected to an LCR series circuit. Which one of the following graphs correctly represents variation of impedance Zof a.c. circuit with angular frequency omega ?

    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

    Home
    Profile