Home
Class 12
PHYSICS
The potentiometer wire AB is 600 cm long...

The potentiometer wire `AB` is `600` cm long.
a. At what distance from A should be jockey `J` touch the wire to get zero deflection i the galvanometer.
b. If the jockey touches the wire at a distance `560 cm` from A, what will be the current through the galvanometer.

Text Solution

Verified by Experts

The correct Answer is:
`320 cm` b. (3 epsilon)/(22r)`

Current in `AB`, `I = (E)/(r + 15 r) = (E)/(16 r)`
Potential gradient, `k = (15 rI)/(600) = (15 r)/(600) xx (E)/(16r) = (E)/(640)`
Let `E//2` be balanced at `l` then
`(E)/(2) = kl = (E)/(640)l` or `l= 320 cm`
b. Let potential at `C` be zero and at `A` be x. Then applying kirchhoff's first law at `C`, we get
`(x - 0)/(14r) + ((x - E)//(2 - 0))/(r) + ((x - E - 0))/(2r) = 0`
or `x = (14 E)/(22)`
`I_(g) = (x - (E)/(2))/(r) = (((14 E)/(22)) - (E)/(2))/(r) = (3E)/(22r)`
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • ELECTRICAL MEASURING INSTRUMENTS

    CENGAGE PHYSICS|Exercise Single Correct|94 Videos
  • ELECTRICAL MEASURING INSTRUMENTS

    CENGAGE PHYSICS|Exercise Multiple Correct|7 Videos
  • ELECTRICAL MEASURING INSTRUMENTS

    CENGAGE PHYSICS|Exercise Exercise 6.1|15 Videos
  • ELECTRIC POTENTIAL

    CENGAGE PHYSICS|Exercise DPP 3.5|14 Videos
  • ELECTROMAGENTIC INDUCTION

    CENGAGE PHYSICS|Exercise QUESTION BANK|40 Videos

Similar Questions

Explore conceptually related problems

The potentiometer wire AB is 600cm long. At what distance (in cm) from A should the jockey J touch the wire to get zero deflection in the galvanometer?

Consider the potentiometer circuit arranged as in figure.The petentiometer wire is 600cm long.(a) At wht distance from the point A should the jockey touch the wire to get zero deflection in the galvanometer?(b) If the jockey touches the wire at a distance of 560cm from A, What will be the current in the galvanometer?

Knowledge Check

  • What is the magnetic induction at a distance of 5 cm from a straight wire carrying a current of 5 mA ?

    A
    `4xx10^(-8)Wb//m^(2)`
    B
    `3xx10^(-8)Wb//m^(2)`
    C
    `2xx10^(-8)Wb//m^(2)`
    D
    `5.5 xx10^(-8)Wb//m^(2)`
  • Similar Questions

    Explore conceptually related problems

    A potentiometer wire AB is 100 cm long and has total resistance of 10Omega . If the galvanometer shows zero deflection at the position C , then find value of unknown resistance

    The potentiometer wire AB shown in figure. Is 40 cm long. Where should the free end of the galvanometer be connected on AB so that the galvanometer may show zero deflection?

    The potentiometer wire AB shown in figure is 40 cm long. Where should the free end of the galvanometer be connected on AB so that the galvanometer may show zero deflection?

    A thin uniform wire AB of length 1m , an unknown resistance X and a resistance of 12 Omega are connected by thick conducting strips, as shown in the figure. A battery and a galvanometer (with a sliding jockey connected to it) area also available. Connections are to be made to measure the unknown resistance X using the principle of Wheatstone bridge. Answer the following questions. (a) Are there positive and negative terminals on the galvanometer ? (b) Copy the figure in your answer book and show the battery and the galvanometer (with jockey) connected at apalphariate points. ( c) After apalphariate connections are made, it is found that no deflection takes place in the galvanometer when the sliding jockey touches the wire at a distance of 60 cm from A . Obtain the value of the resistance X .

    The potentiometer wire AB shown in figure is 40 cm long. Where the free end of the galvanometer should be connected on AB so that the galvanometer may show zero deflection?

    A thin uniform wire AB of length 1 m, an unknown resistance X and a resistance of 12Omega are connected by thick conducting strips, as shown in the figure. A battery and a galvanometer (with a sliding jockey connected to it) are also available connections are to be made to measure the unknown resistance X using the principle of Wheatstone bridge. Answer the following questions. (a) Are there positive and negative terminals on the galvanometer? (b) Copy the figure in your answer book and show the battery and the galvanometer(with jockey) connected at appropriate points. (c) After appropriate connections are made, it is found that no deflection takes place in the galvanometer when the sliding jockey touches the wire at a distance of 60 cm from A. Obtain the value of the resistance of X

    A thin uniform wire AB of length 1 m , an unknown resistance X and a resistance of 12 Omega are connected by thick conducting strips, as shown in the figure. A battery and a galvanometer (with a sliding jockey connected to it) are also available. Connections are to be made to measure the unknown resistance X . Using the principle of Wheatstone bridge answer the following questions : (a) Are there positive and negative terminals on the galvanometer? (b) Copy the figure in your answer book and show the battery and the galvanometer (with jockey connect at appropriate points. (c) After appropriate connections are made, it is found that no deflection takes place in th, from galvanometer when the sliding jockey touches the wire at a distance of 60 cm from A . Obtain value of the resistance X.