Match List I with List II
| LIST I Devices | LIST II Working Principle | ||
|---|---|---|---|
| A. | Transformer | I. | Wheatstone Bridge |
| B. | Meter Bridge | II. | Electromagnetic Induction |
| C. | Moving Coil Galvanometer | III. | Mutual Induction |
| D. | A.C Generator | IV. | Torque on a current carrying coil |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → A-III, B-I, C-IV, D-II
Each device is built on one working principle, and the match is found by asking which physical effect makes the device work.
(A) Transformer — this matches (III) Mutual Induction. A changing current in the primary coil changes the flux linked with the secondary coil and induces an emf in it.
(B) Meter Bridge — this matches (I) Wheatstone Bridge. It is the Wheatstone bridge with the two ratio arms made from one uniform wire, balanced by a sliding contact.
(C) Moving Coil Galvanometer — this matches (IV) Torque on a current carrying coil. A current-carrying coil in a magnetic field experiences a torque that turns the pointer against a spring.
(D) A.C Generator — this matches (II) Electromagnetic Induction. A coil rotated in a magnetic field has a changing flux linked with it, so an emf is induced.
NCERT (2026-27):
Transformers – “… This is done with a device called transformer using the principle of mutual induction.”
Wheatstone Bridge – “… The Wheatstone bridge and its balance condition provide a practical method for determination of an unknown resistance. … A practical device using this principle is called the meter bridge.”
The Moving Coil Galvanometer – “… The magnetic torque NIAB tends to rotate the coil.”
AC Generator – “The phenomenon of electromagnetic induction has been technologically exploited in many ways. An exceptionally important application is the generation of alternating currents (ac).”