This is a potentiometer circuit.

a i. Sketch a graph of reading on the voltmeter against length, l, as the jockey is moved from point A to point B.

ii. State the readings on the voltmeter when the jockey is connected to A and when it is connected to B. (You may assume that the driver cell has negligible internal resistance.)

iii. Draw a circuit diagram to show how the potentiometer could be used to compare the e.m.f.s of two batteries.

b. When a pair of 4 Ω resistors are connected in series with a battery, there is a current of 0.60 A current through the battery. When the same two resistors are connected in parallel and then connected across the battery, there is a current of 1.50 A through it. Calculate the e.m.f. and the internal resistance of the battery.

Transcribed Image Text:

E, = 2.2 V V jockey uniform resistance wire Figure 11.18