NEET Physics Galvanometer and its Conversion into Ammeter and Voltmeter MCQs Set 01

Question. The AC voltage across a resistance can be measured using a
(a) moving coil galvanometer
(b) potential coil galvanometer
(c) moving magnet galvanometer
(d) hot wire voltmeter

Answer: A

Question. The deflection in a moving coil galvanometer is
(a) directly proportional to the number of turns in the coil
(b) inversely proportional to the area of the coil
(c) inversely proportional to the current flowing
(d) directly proportional to the torsional constant

Answer: A

Question. A moving coil galvanometer has N number of turns in a coil of effective area A, it carries a current I. The magnetic field B is radial. The torque acting on the coil is
(a) NABI
(b) N²ABI
(c) None of these
(d) NABI²

Answer: A

Question. The current sensitivity of a galvanometer is defined as
(a) deflection per unit current.
(b) current per unit deflection
(c) dflection per unit current when a unit voltage is applied across its terminals
(d) the current flowing through the galvanometer when a unit voltage is applied across its terminals.

Answer: A

Question.  The galvanometer cannot as such be used as an ammeter to measure the value of current in a given circuit. The following reasons are
I. galvanometer gives full scale deflection for a small current.
II. galvanometer has a large resistance.
III. a galvanometer can give inaccurate values.
The correct reasons are:
(a) I and II
(b) II and III
(c) I, II and III
(d) I and III

Answer: A

Question. Assertion: To convert a galvanometer into an ammeter a small resistance is connected in parallel with it.
Reason: The small resistance increases the combined resistance of the combination
(a) Assertion is correct, reason is correct; reason is a correct explanation for assertion
(b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
(c) Assertion is correct, reason is incorrect
(d) Assertion is incorrect, reason is correct

Answer: A

Question. A galvanometer having a resistance of 80 ohms is shunted by a wire of resistance 2 ohms. If the total current is 1amp., the part of it passing through the shunt will be
(a) 0.02 amp
(b) 0.5 amp
(c) 0.8 amp
(d) 0.25 amp

Answer: A

Question. A galvanometer of resistance 5 ohms gives a full scale deflection for a potential difference of 10 mV. To convert the galvanometer into a voltmeter giving a full scale deflection for a potential difference of 1V, the size of the resistance that must be attached to the voltmeter is
(a) 495 ohm
(b) 49.5 ohm
(c) 4950 ohm
(d) None of these

Answer: A