Get Answers to all your Questions

header-bg qa

Shown in the figure below is a meter­bridge set up with null deflection in the galvanometer. The value of the unknown resistance  R is :

  • Option 1)

    55\Omega

  • Option 2)

    13.75 \Omega

  • Option 3)

    220 \Omega

  • Option 4)

    110 \Omega

 

Answers (1)

best_answer

As we learnt in

Wheat stone Bridge -

It is an arrangement of four resistances which can be used to measure one of them in terms of rest

- wherein

 

 

 

This is a Wheatstone bridge.

If   \rho _{l}   is the resistance per unit length (in cm)

\frac{20\rho _{l}}{55}= \frac{80\rho _{l}}{R}\: \: or \: \: R= \frac{80\times 55}{20}= 220\Omega


Option 1)

55\Omega

This option is incorrect.

Option 2)

13.75 \Omega

This option is incorrect.

Option 3)

220 \Omega

This option is correct.

Option 4)

110 \Omega

This option is incorrect.

Posted by

Plabita

View full answer

JEE Main high-scoring chapters and topics

Study 40% syllabus and score up to 100% marks in JEE