Question

(a) Draw a labellel diagram of a moving coil galvanometer. Describe briefly its principle and working.
(b) Answer the following:
(i) Why is it necessary to introduce a cyclindrical soft iron core inside the coil of a galvanometer?
(ii) Increasing the current sensitivity of galvanometer may not necessarily increase its voltage sensitivity. Explain, giving reason.

Answer 1

(a) Principle and working : A current carrying coil, placed in a uniform magnetic field, (can) experience a torque Consider a rectangular coil for which no. of turns = N.
(b) (i) The soft iron core not only makes the field radial but also increases the strength of the magnetic field.
(ii)