Home
Class 12
PHYSICS
A potentiometre wire is 100 cm long and...

A potentiometre wire is 100 cm long and a constant potential difference is maintained across it. Two cells are connected in series first to support one another and then in opposite direction.The balance points are obtained at 50 cm and 10 cm from the positive end of the wire in two cases. The ration of emf's is

A

`3 : 2`

B

`5 : 1`

C

`5 : 4`

D

`3 : 4`

Text Solution

Verified by Experts

Promotional Banner

Topper's Solved these Questions

  • ATOMS AND NUCLEI

    SARAS PUBLICATION|Exercise EXAMPLE|36 Videos

  • DUAL NATURE OF MATTER AND RADIATION

    SARAS PUBLICATION|Exercise EXAMPLE|27 Videos

Similar Questions

Explore conceptually related problems

Two long and parallel street wires carrying current of 2A and 5A in the opposite direction are separated by a distance of 1 cm. Find the nature and magnitude of the magnetic force between them.

The two long, straight wires carrying electric currents of 10A each in opposite directions. The separation between the wires is 5.0 cm. Find the magnetic field at a point P midway between the wires.

A potentiometer wire of length 100 cm has a resistance of 10Omega .It is connected in series with a resistance and a cell of emf 2V having negligible internal resistance.A source of emf 10 mV is balanced against a length of 40 cm of the potentiometer wire. The value of external resistance is

A potentiometre wire has length 4m resistance 8 Omega . The resistance that must be connected in series with the wire and an accumulator of e.m.f. 2v, so as to get a potential gradient 1 mV per cm on the wire is:

A potentiometer wire has a length 400 cm and a resistance of 20 Omega . It is connected in series with an external resistance R and a cell of e.m.f. 1.5 V and internal resistance 1 Omega . A source of e.m.f.6 mV is balanced against a length of 30 cm of the potentiometer wire. Find R. According to the principle of potentiometer Vpropl . i.e., V = ilp where l'is the balancing length & p the resistance per cm of the potentiometer wire.

Two long parallel straight wires X and Y separated by a distance of 5 cm in air carry currents of 10A and 5A respectively in opposite directions. Calculate the magnitude and direction of the force on a 20 cm length of the wire Y.

A particle is in linear simple harmonic motion between two points, A and B, 10 cm apart. Take the direction from A to B as the positive direction and give the signs of velocity, acceleration and force on the particle when it is at the end A.

A particle is in linear simple harmonic motion between two points, A and B, 10 cm apart. Take the direction from A to B as the positive direction and give the signs of velocity, acceleration and force on the particle when it is at the end B.

SARAS PUBLICATION-CURRENT ELECTRICITY-EXAMPLE
  1. The resistance of the four arms P,Q,R and S in a Wheatstone's bridge a...

    Text Solution

    |

  2. In the adjacent figure. AC = 6 cm, AB = 5 cm and angleBAC = 30^(@). Fi...

    Text Solution

    |

  3. Two rods are joined end to end as shown. Both have a cross-sectional a...

    Text Solution

    |

  4. A conducting sphere of radius R is given a charge Q.The electric poten...

    Text Solution

    |

  5. The resistances in the two arms of the metre bridge are 5Omega and R O...

    Text Solution

    |

  6. A potentiometer circuit has been set up for finding the internal resis...

    Text Solution

    |

  7. A potentiometer wire of length L and a resistance r are connected in s...

    Text Solution

    |

  8. Across a metallic conductor of non- uniform cross section a constant p...

    Text Solution

    |

  9. A potentiometre wire has length 4m resistance 8Omega. The resistance t...

    Text Solution

    |

  10. A,B and C are voltmetres of resistance R, 1.5R and 3R as shown in the ...

    Text Solution

    |

  11. An inductor 20 mH , a capacitor 50mu F and a resistor 40 are connected...

    Text Solution

    |

  12. A potentiometre wire is 100 cm long and a constant potential differen...

    Text Solution

    |

  13. A capacitor of 2mu F is charged as shown in the diagram. When the swit...

    Text Solution

    |

  14. If the velocity of a particle is nu=At+Bt^2, where A and B are constan...

    Text Solution

    |

  15. The charge flowing through a resistance R varies with time t as Q=at-b...

    Text Solution

    |

  16. A filament bulb (500W, 100V)is to be used in a 230v main supply. When ...

    Text Solution

    |

  17. The given circuit has two ideal diodes connected as shown in the figur...

    Text Solution

    |

  18. The temperature inside a refrigator is t2^@C and the room temperature ...

    Text Solution

    |

  19. The resistance of a wire is 'R' ohm. If it is melted and stretched to ...

    Text Solution

    |

  20. A potentiometer is an accurate and versatile device to make electrical...

    Text Solution

    |