Q1 The best instrument for accurate measurement of emf of a cell is
- a) Wheatstone bridge
- b) ammeter
- c) potentiometer
- d) voltmeter
- c) potentiometer
Q2 The material used to make potentiometer wire normally is
- a) Constantan or manganin
- b) nickel
- c) Copper
- d) zinc
- a) Constantan or manganin
Q3 In order to achieve high accuracy the slide wire of a potentiometer should be ?
- a) as long as possible
- b) as short as possible
- c) neither to small nor too long
- d) very thick
- a) as long as possible
Q4 A potentiometer is a device for
- a) comparing two voltages
- b) measuring current
- c) comparing current
- d) none of the above
- a) comparing two voltages
Q5 A potentiometer is used to measure the emf of a cell. At null point, no current flow through..
- a) the main circuit
- b) the cell circuit
- c) both main and cell circuit
- d) the potentiometer wire
- b) the cell circuit
Q6 The fall of potential per unit length of wire is called.......
- (a) Potential difference
- (b) Potential gradient
- (c) both (a) and (b)
- (d) None of these
- (b) Potential gradient
Q7 The sensitivity of a potentiometer can be increased by
- (a) Increasing e.m.f of primary cell
- (b) Increasing potential gradient
- (c) Increasing length of potentiometer wire
- (d) Decreasing length of potentiometer wire
- (c) Increasing length of potentiometer wire
Q8 Which one of the following is a disadvantage of a potentiometer over a voltmeter?
- (a) It can measure internal resistance of a cell
- (b) It can measure e.m.f of a cell
- (c) It is heavy and not portable
- (d) It can measure very accurately small potential differences of few Microvolts.
- c) It is heavy and not portable
Q9. If the length of a potentiometer wire is doubled, the accuracy in determining null point will be
- Zero
- increases
- decreases
- No any effect
- increases
Q10 The instrument used for the accurate measurement of the e.m.f of cell is
- Wheatstone Bridge
- Slide wire bridge
- Potentiometer
- None of these
- Potentiometer
