As shown in the diagram, an electric circuit consisting of an ammeter, a voltmeter, 4 cells of 1·5 V each, a plug key with a gap XY was set up. Voltmeter and ammeter readings were recorded in the observation table for four arrangements as given below : Arrangement No. 1 – only resistor R1 in gap…

Question

As shown in the diagram, an electric circuit consisting of an ammeter, a voltmeter, 4 cells of 1·5 V each, a plug key with a gap XY was set up. Voltmeter and ammeter readings were recorded in the observation table for four arrangements as given below : Arrangement No. 1 – only resistor R1 in gap XY Arrangement No. 2 – only resistor R2 in gap XY Arrangement No. 3 – Resistors R1 and R2 in series in gap XY Arrangement No. 4 – Resistors R1 and R2 in parallel in gap XY Based on the observations, four V – I graphs A, B, C and D as shown in figure were drawn. Study these graphs. (a) Which one of the graphs represents the series combination of R1 and R2 ? (b) Which one of these graphs represents the parallel combination of R1 and R2 ? (c) (i) Show an arrangement of three resistors, each of resistance 10 Ω, so that the combination has a resistance of 15 Ω. Give justification for your answer.

Aicharya · Accepted Answer

(a) Graph A (b) Graph D (c) (i) [diagram: two 10 Ohm resistors in parallel, in series with a third 10 Ohm resistor] R = R1R2/(R1+R2) + R3 R = (10 × 10/(10+10) + 10) Ohm = 5 Ohm + 10 Ohm = 15 Ohm

As shown in the diagram, an electric circuit consisting of an ammeter, a voltmeter, 4 cells of 1·5 V each, a…

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