In a meter bridge, point D is a neutral point as shown in the figure.
a. | The meter bridge can have no other neutral point for this set of resistances. |
b. | When the jockey contacts a point on the meter wire left of D, current flows to B from the wire. |
c. | When the jockey contacts a point on the meter wire to the right of D, current flows from B to the wire through the galvanometer. |
d. | When R is increased, the neutral point shifts to left. |
Which of the above statements is correct?
1. (a, c)
2. (a, d)
3. (b, c)
4. (c, d)
A resistance R is to be measured using a meter bridge. A student chooses the standard resistance S to be 100 . He finds the null point at l1 = 2.9 cm. He is told to attempt to improve accuracy. Which of the following is a useful way?
1. | He should measure l1 more accurately |
2. | He should change S to 1000 Ω and repeat the experiment |
3. | He should change S to 3 Ω and repeat the experiment |
4. | He should give up hope of more accurate measurement with a meter bridge |
Two cells of emf's approximately \(5\) V and \(10\) V are to be accurately compared using a potentiometer of length \(400\) cm.
1. | The battery that runs the potentiometer should have a voltage of \(8\) V |
2. | The battery of the potentiometer can have a voltage of \(15\) V and \(R\) adjusted so that the potential drop across the wire slightly exceeds \(10\) V |
3. | The first portion of \(50\) cm of the wire itself should have a potential drop of \(10\) V |
4. | Potentiometer is usually used for comparing resistances and not voltages |