Home
Class 12
PHYSICS
Suppose the resistance of the coil in th...

Suppose the resistance of the coil in the previous problem is `25Omega`. Assume that the coil moves with uniform velocity during its removal and restoration. Find the thermal energy developed in the coil during (a) its removal, (b) its restoration and (c) its motion.

Text Solution

Verified by Experts

Here `R=25 W`
`(a) a=50V , T=0.25s`
`i=e/R=2A`
`H=I^2 RtT`
`=4xx25xx0.25=25J`
`(b) e=50v, T=0.25s`
`i=(e/R)=2A`
`H=i^2 RT=25 J`
`(c ) Since energy is a scalar quantity `
`:, Net thermal energy developed `
`=25J+25J=50J.`
Promotional Banner

Topper's Solved these Questions

  • ELECTROMAGNETIC INDUCTION

    HC VERMA|Exercise EXERCISE|9 Videos

  • ELECTROMAGNETIC INDUCTION

    HC VERMA|Exercise Objective 2|10 Videos

  • ELECTRIC FIELD AND POTENTIAL

    HC VERMA|Exercise Exercises|75 Videos

  • ELECTROMAGNETIC WAVES

    HC VERMA|Exercise Exercises|9 Videos

Similar Questions

Explore conceptually related problems

A ball is released from point A. During its motion ball takes two seconds from B to C Find the time taken by ball from A to C. .

An object A is kept fixed at the point x= 3 m and y = 1.25 m on a plank p raised above the ground . At time t = 0 the plank starts moving along the +x direction with an acceleration 1.5 m//s^(2) . At the same instant a stone is projected from the origin with a velocity vec(u) as shown . A stationary person on the ground observes the stone hitting the object during its downward motion at an angle 45(@) to the horizontal . All the motions are in the X -Y plane . Find vec(u) and the time after which the stone hits the object . Take g = 10 m//s

Earth's orbit is an ellipse with eccentricity 0.0167. Thus the earth's distance from the sun and speed as it moves around the sun varles from day-to-day. This means that the length of the solar day is not constant through the year. Assume that the earth's spin axis is normal to its orbital plane and find out the length of the shortest and the longest day. A day should be taken from noon to noon. Does this explain variation of length of the day during the year?

Figure shows a metal rod PQ resting on the smooth rails AB and positioned between the poles of a permanent magnet. The rails, the rod, and the magnetic field are in three mutual perpendicular directions. A galvanometer G connects the rails through a switch K. Length of the rod =15 cm, B =0.50 T, resistance of the closed loop containing the rod 9.0 m Omega . Assume the field to be uniform. (a) Suppose K is open and the rod is moved with a speed of 12 "cm s"^(-1) in the direction shown. Give the polarity and magnitude of the induced emf. (b) Is there an excess charge built up at the ends of the rods when K is open ? What if K is closed ? (c) With K open and the rod moving uniformly, there is no net force on the electrons in the rod PQ even though they do experience magnetic force due to the motion of the rod. Explain. (d) What is the retarding force on the rod when K is closed ? How much power is required (by an external agent) to keep the rod moving at the same speed (= 12 cm s^(-1) ) when K is closed ? How much power is required when K is open? (f)How much power is dissipated as heat in the closed circuit ? What is the source of this power ? (g) What is the induced emf in the moving rod if the magnetic field is parallel to the rails instead of being perpendicular ?

A 100 turn closely wound circular coil of radius 10 cm carries a current of 3.2 A. (a) What is the field at the centre of the coil? (b) What is the magnetic moment of this coil? The coil is placed in a vertical plane and is free to rotate about a horizontal axis which coincides with its diameter. A uniform magnetic field of 2T in the horizontal direction exists such that initially the axis of the coil is in the direction of the field. The coil rotates through an angle of 90^@ under the influence of the magnetic field. (c) What are the magnitudes of the torques on the coil in the initial and final position? (d) What is the angular speed acquired by the coil when it has rotated by 90^@ ? The moment of inertia of the coil is 0.1 kg m^2 .

It is desired to measure the magnitude of field between the poles of a powerful loud speaker magnet. A small flat search coil of area 2 "cm"^2 with 25 closely wound turns, is positioned normal to the field direction, and then quickly snatched out of the field region. Equivalently, one can give it a quick 90^@ turn to bring its plane parallel to the field direction). The total charge flown in the coil (measured by a ballistic galvanometer connected to coil) is 7.5 mC. The combined resistance of the coil and the galvanometer is 0.50 Omega . Estimate the field strength of magnet.

Acceleration of a particle moving along the x-axis is defined by the law a=-4x , where a is in m//s^(2) and x is in meters. At the instant t=0 , the particle passes the origin with a velocity of 2 m//s moving in the positive x-direction. (a) Find its velocity v as function of its position coordinates. (b) find its position x as function of time t. (c) Find the maximum distance it can go away from the origin.

Acceleration of particle moving along the x-axis varies according to the law a=-2v , where a is in m//s^(2) and v is in m//s . At the instant t=0 , the particle passes the origin with a velocity of 2 m//s moving in the positive x-direction. (a) Find its velocity v as function of time t. (b) Find its position x as function of time t. (c) Find its velocity v as function of its position coordinates. (d) find the maximum distance it can go away from the origin. (e) Will it reach the above-mentioned maximum distance?

HC VERMA-ELECTROMAGNETIC INDUCTION-Exercises
  1. A coducting circular loop of area 1mm^2 is placed coplanarly with a lo...

    Text Solution

    |

  2. A square- shaped copper coil has edges of length 50cm and contains 50 ...

    Text Solution

    |

  3. Suppose the resistance of the coil in the previous problem is 25Omega....

    Text Solution

    |

  4. A conducting loop of area 5.0 cm^2 is placed in a magnetic feld which ...

    Text Solution

    |

  5. Shows a conducting square loop placed parallel to the pole faces of a ...

    Text Solution

    |

  6. A conducting square loop having edges of length 2.0 cm is rotated thro...

    Text Solution

    |

  7. A conducting loop of face area A and resistance R is plaed perpendicul...

    Text Solution

    |

  8. A long slenoid of radius 2 cm has 100 turns/cm and carries a current o...

    Text Solution

    |

  9. The north pole of a magnet is brought down along the axis of a horizon...

    Text Solution

    |

  10. Shown a square loop of side 5 cm beign moved towards right at a consta...

    Text Solution

    |

  11. Find the total heat produced in the loop of the previous problem durin...

    Text Solution

    |

  12. A unifrom magnetic field B exists in a cylindrical region of radius 10...

    Text Solution

    |

  13. The magnetic field in the cylindrical region shown in increases at a ...

    Text Solution

    |

  14. A circular coil of radius 2.00 cm has 50 turns. A uniform magnetic fie...

    Text Solution

    |

  15. A closed coil having 100 turns is rotated in a uniform magnetic field ...

    Text Solution

    |

  16. A coil of radius 10 cm and resistance 40 Omega has 1000 turns. It is ...

    Text Solution

    |

  17. shows a circular wheel of radius 10.0 cm whose upper half, shown dark...

    Text Solution

    |

  18. A 20 cm long conducting rod is set into pure translation with a unifor...

    Text Solution

    |

  19. A metallic metre sitck moves with a velocity of 2 ms ^(-1) in a direc...

    Text Solution

    |

  20. A 10 m wide spaceraft moves through the interstellar space at a speed ...

    Text Solution

    |