Home
Class 12
PHYSICS
An inductor is connected in series with ...

An inductor is connected in series with a bulb to an a.c source. What happens to brighness of bulb when number of turns in the inductor is reduced ?

Text Solution

Verified by Experts

Current through the bulb
`I_(v) = (E_(v))/(Z) = (E_(V))/(sqrt(R^(2) + X_(L)^(2)))`, where `X_(L) = omega L`
As `L prop N^(2)`, therefore, on decreasing number of turns, L decreases , Z decreases, `I_(v)` increases.
Hence brightness of bulb increases.
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • ELECTROMAGNETIC INDUCTION & ALTERNATING CURRENT

    PRADEEP|Exercise Solved Examples (b)|1 Videos

  • ELECTROMAGNETIC INDUCTION & ALTERNATING CURRENT

    PRADEEP|Exercise Short Answer Qusetions|2 Videos

  • DUAL NATURE OF RADIATION AND MATTER

    PRADEEP|Exercise Exercise|191 Videos

  • ELECTROMAGNETIC WAVES

    PRADEEP|Exercise II Focus multiple choice question|5 Videos

Similar Questions

Explore conceptually related problems

An inductor L of inductance X_(L) is connected in series with a bulb B and an AC source . How would brightness of the bulb change when (i) number of turns in the inductor is increased (ii) an iron rod is inserted in the inductor and (iii) a capacitor of reactance X_(C)=X_(L) is inserted in series .

(i) When an AC source is connected to an ideal inductor show that the average power supplied by the source ever a complete cycle is zero. (ii) A lamp is connected in series with an inductor and an AC source. What happens to the brightness of the lamp when the key is plugged in and an iron rod is inserted the indcutor ? Explain.

Knowledge Check

  • An inductor and a resistor are connected in series with an ac source. In this circuit.

    A
    the current and the PD across the resistance lead the PD across the inductance
    B
    the current and the PD across the resistance lag behind the PD across the inductance by an angle `(pi)//(2)`.
    C
    the current and the PD across the resistance lag behind the PD across the inductance by an angle `(pi)`.
    D
    the PD across the resistance lag behind the PD across the inductance by an angle `(pi)//(2)` but the current in resistance leads the PD across the inductance by `(pi)//(2)`.

  • A coil of self inductance L is connected in series with a bulb and an A.C. source. Brightness of the bulb decreases when

    A
    Number of turns in the coil is reduced
    B
    A capacitance of reactance `X_(c) = X_(L)` is included in the same circuit
    C
    An iron rod is inserted in the coil
    D
    Frequency of the A.C. source is decresed

  • A coil of self-inductance L is connected in series with a bulb B and an AC source. Brightness of the bulb decreases when

    A
    Frequency of the `AC` source is decreased
    B
    Number of turns in the coil is reduced
    C
    A capacitance of reactance `X_(C)=X_(L)` is included in the same circuit
    D
    An iron rod is inserted in the coil

    • Similar Questions

    Explore conceptually related problems

    An electric bulb is connected in series with an inductor and an Ac source. When switch is closed. After sometime an iron rod is inserted into the interior of inductor. How will the brightness of bulb be affected? Justify your answer.

    A bulb and a capacitor are connected in series to an a.c. source of varialbe frequency. How will the brightness of the bulb change on increasing the frequency of a.c. source ?

    A bulb and a capacitor are connected in series to an a.c. source of variable frequency. How will the brightness of the bulb change on increasing the frequency of the a.c. source. Give reason.

    A capacitor of 100 muF , a resistor of 20 Omega and an inductor of inductance L are connected in series with an a.c. source of frequency 50 Hz. Calculate the value of inductance L of the inductor, if phase angle between current and voltage is zero.

    A lamp is connected is series with a a capacitor and an AC source, what happens if the capacity of the capacitor is reduced ?

    Home
    Profile