What is the voltage across six 1.5-V batteries when they are connected (a) in series, (b) in parallel, (c) three in parallel with one another and this combination wired in series with the remaining three?

(a) 9.0 V (b) 1.5 V (c) 6.0 V

Explanation:

Here we use the simple concept of Kirchhoff's voltage law that potential in series will be added and potential in parallel will be same always. By this concept we answer all 3 parts of this question.

(a) When six 1.5 V batteries are is series means their potential is added.

So, Voltage across six batteries is

So, Net voltage is 9.0 Volts.

(b)When six 1.5 V batteries are in parallel then the net voltage across them will be voltage of either battery.

So, Voltage is

Net voltage is 1.5 Volts.

(c) Now 3 are in series and 3 are in parallel,

the Net voltage of parallel is 1.5 V , now it behaves like four 1.5 V are in series so the net voltage become

Net voltage is 6.0 Volts.

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