Home
Class 12
PHYSICS
Assertion: Potentiometer measures correc...

Assertion: Potentiometer measures correct value of emf of a cell.
Reason: No current flows through cell at null point of potentiometer.

A

If both Assertion `&` Reason are True `&` the Reason is a correct explanantion of the Assertion

B

If both Assertion `&` Reason True but Reason is not a correct explanation of the Assertion

C

If Assertion is True but the Reason is False

D

If both Assertion `&` Reason are False.

Text Solution

Verified by Experts

The correct Answer is:
1
Promotional Banner

Topper's Solved these Questions

  • CURRENT ELECTRICITY

    ALLEN|Exercise EXERCISE-V B|20 Videos

  • CIRCULAR MOTION

    ALLEN|Exercise EXERCISE (J-A)|6 Videos

  • GEOMETRICAL OPTICS

    ALLEN|Exercise subjective|14 Videos

Similar Questions

Explore conceptually related problems

The current flowing through the cell in the circuit shown is

Assertion A potentiometer is preferred over that of a voltmeter for measurement of emf of a cell Reason potentiometer does not draw any current from the cell.

It is observed in a potentiometer experiment that no current passes through the galvanometer, when the terminals of the potentiometer, wire. On shunting the cell by a 2Omega resistance, the balancing length is reduced to half. The internal resistance of the cell is:-

Assertion : Potentiometer is used only to compare potential differences. Reason: The potentiometer draws current from the voltage source being measured .

The wire of potentiometer has resistance 4 Omega and length 1m. It is connected to a cell of e.m.f. 2V and internal resistance 1 Omega . The current flowing through the potentiometer wire is

Why do we prefer a potentiometer to measure emf of a cell rather than a voltmeter ?

Assertion : The e.m.f. of the drivercell in the potentiometer experiment should be greater than the e.m.f. of the cell to determined. reason ; the fall of potential across the potentiometer wire should not be less than the emf of the cell to be determined.

Assertion : In case of potentiometer experiment, if emfs of known and unknown both batteries are increased two times, then null point length will remain unchanged. Reason : Null point length does not depend on emf of either of the two batteries.

A : parctically a voltmeter will measure the voltage across the battery but not its EMF. R : EMF of a cell is measured with the help of a potentiometer .

The circuit shows in Fig . 6.33 shows the use of potentiometer to measure the internal resistance of a cell. (a) When the key is open, how does the balance point change, if the driver cell decreases ? (b) When the key is closed, how does the balance point change, if R is increased, keeping the current from the driver cell constant ?

ALLEN-CURRENT ELECTRICITY-EX.II
  1. In the arrangement of resistances shown below, the effective resistanc...

    Text Solution

    |

  2. A potentiometer wire of length 100cm has a resistance of 10Omega. It i...

    Text Solution

    |

  3. Electromotive force of a cell is basically a

    Text Solution

    |

  4. A battery of emf 10 V and internal resistance 0.5 Omega is connected a...

    Text Solution

    |

  5. A galvanometer has resistance G and Current I(g) produces full scale d...

    Text Solution

    |

  6. In a neon discharge tube 2.9 xx 10^(18) Ne^(+) ions move to the right ...

    Text Solution

    |

  7. When a resistance of 2 ohm is connected across terminals of a cell, th...

    Text Solution

    |

  8. Two nonideal batteries are connected in parallel. Consider the followi...

    Text Solution

    |

  9. The current in 8Omega resistance is (as per given circuit)

    Text Solution

    |

  10. Assertion : Electric field inside a hollow sphere conductor is 0. Rea...

    Text Solution

    |

  11. Assertion: A voltmeter must b e connected in parallel in a circuit and...

    Text Solution

    |

  12. Assertion : Electric field outside the conducting wire which carreis a...

    Text Solution

    |

  13. Assertion:- Kirchhoff's voltage law indicates that field is conservati...

    Text Solution

    |

  14. Assertion: Terminal potential difference of a cell is always less than...

    Text Solution

    |

  15. Assertion: When wheatstone bridge is balanced then current through cel...

    Text Solution

    |

  16. Assertion: Potentiometer measures correct value of emf of a cell. Re...

    Text Solution

    |

  17. Assertion : When cells are connected in parallel to the external loa...

    Text Solution

    |

  18. Potentiometer wire is made of manganin because it has

    Text Solution

    |

  19. Assertion: meterbridge wire is made up of manganin Reason: The tempe...

    Text Solution

    |

  20. Assertion: Current is a scalar quantity. Reason: Electric current a...

    Text Solution

    |