Question

In the context of a PMMC instrument, identify the correct matches:

List - I	List - II
(i) a pair of springs	(p) to provide controlling torque
(ii) aluminimum former	(q) to provide damping torque
	(r) to act as a base for the coil
	(s) to provide current into and out of the moving coil

• A. (i) - (p) and (q), (ii) - (r) and (s)
• B. (i) - (r) and (s), (ii) - (p) and (q)
• C. (i) - (p) and (s), (ii) - (q) and (r)
• D. (i) - (q) and (r), (ii) - (p) and (s)

Answer 1

The correct option is C (i) - (p) and (s), (ii) - (q) and (r)

In PMMC, spring is used to
(i) Provide controlling torque.
(ii) Provide current into and out of moving coil and this is the reason why pointer points to zero (null) if spring is snapped (broken).

Aluminium former is used in PMMC to,

(i) Provide damping torque by producing eddy currents.
(ii) Also acts as base of coil.