Home
Class 12
PHYSICS
In Fig. ABCD is a fixed smooth conductin...

In Fig. `ABCD` is a fixed smooth conducting frame in horizontal plane. `T` is bulb of power `100 W , P` is a smooth pulley and `OQ` is a conducting rod. Neglect the self-inductance of the loop and resistance of any part other than the bulb. The mass `M` is moving down with constant velocity `10 ms^(-1)`. Bulb lights at its rated power due to induced emf in the loop due to earth's magnetic field. Find the mass `M` (in kg) of teh block. (g = 10 ms^(2))`

Text Solution

Verified by Experts

The correct Answer is:
1

The rate of electrical energy consumed in the bulb = rate of loss of gravitational `PE` of the mass `= Mgv = 100 W`. Hence `M = (100)/(10 xx 10) = 1 kg`s
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • ELECTROMAGNETIC INDUCTION

    CENGAGE PHYSICS|Exercise Archives Fill In The Blanks|3 Videos
  • ELECTROMAGNETIC INDUCTION

    CENGAGE PHYSICS|Exercise Archives Single Correct|11 Videos
  • ELECTROMAGNETIC INDUCTION

    CENGAGE PHYSICS|Exercise Exercises Linked Comprehension|36 Videos
  • ELECTROMAGENTIC INDUCTION

    CENGAGE PHYSICS|Exercise QUESTION BANK|40 Videos
  • ELECTRON,PHONTS,PHOTOELECTRIC EFFECT & X-RAYS

    CENGAGE PHYSICS|Exercise dpp 3.3|15 Videos

Similar Questions

Explore conceptually related problems

A bulb is rated 5.0 V, 100 mA. Calculate its rated power and resistance.

A light bulb is rated 200 W for 220 V supply at 50 Hz. Calculate resistance of the bulb and rms current through the bulb.

Knowledge Check

  • A conducting square loop of side L and resistance R moves in its to one of tis sides. A magnetic induction B , constant in time and space, pointing perpendicular to and into the plane of the loop exists every where. The current induced in the loop is

    A
    `Blnu//R` clock wise
    B
    `Blnu //R` anticlockwise
    C
    `2BLnu//R` anticlockwise
    D
    zero
  • A conducting square loop is placed in a magnetic field B with its plane perpendicular to the field. The sides of the loop start shrinking at a constant rate alpha . The induced emf in the loop at an instant when its side is ‘a’ is

    A
    `2a alpha B`
    B
    `a^(2)alphaB`
    C
    `2a^(2)alpha B`
    D
    `a alpha B`
  • A conducting square loop is placed in a magnetic field B with its plane perpendicular to the field. Now the sides of the loop start shrinking at a constant rate alpha. the induced emf in the loop at an instant when its side is a is

    A
    `2aalphaB`
    B
    `a^2alphaB`
    C
    `2a^2alphaB`
    D
    `aalphaB`
  • Similar Questions

    Explore conceptually related problems

    A conducting circular loop is placed is a uniform magnetic field B =0.20 T with its plane perpendicualr to the field . Somehow, the radius of the loop starts shrinking at a constant rate of 1.0 mm s^(-1). Find the induced emf in the loop at an instant when the radius is 2 cm.

    A conducting circular loop is placed in a magnetic field of strength 0.04 T, such that the plane of the loop is perpendicular to the magnetic field. If the radius of the loop begins to shrink at a constant rate of 0.5 mm // s , then calculate the emf induced in the loop when its radius is 1.5 cm.

    Fig. 6.15 shows a current carrying solenoid moving towards a conducting loop. Find the direction of the current induced in the loop.

    L is a smooth conducting loop of radius l=1.0 m & fixed in a horizontal plane. A conducting rod of mass m=1.0 kg and length slightly greater than l hinged at the centre of the loop can rotate in the horizontal plane such that the free end slide on the rim of the loop. There is a uniform magnetic field of strength B=1.0 T directed vertically downward. The rod is rotated with angular velocity omega_(0)=1.0 rad//s and left. The fixed end of the rod and the rim of the loop are connected through a battery of emf . E, a resistor of resistance R =1.0 Omega , and intially uncharged capacitor of capacitance C=1.0 F in series. Find : (i) the time dependence of emf . E such that the current I_(0)=1.0A in the circuit is constant. (ii) energy supplied by the battery by the time rod stops.

    About 5% of the power of a 100 W light bulb is converted to visible radiation. The average intensity of visible radiation at a distance of 1 m from the bulb: