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Question
Which of the following arrangement, A or B, has the lower combined resistance?
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Solution
In figure A, the resistance, RA = 10 Ω
In figure B, the resistors of 10 Ω and 1000 Ω are connected in parallel combination.
Therefore:
`1/R=1/R_1+1/R_2`
`1/R=1/10+1/1000`
or `1/R=100/1000+1/1000`
or`1/R=101/1000`
`R=1000/101=9.9`Ω
RB = 9.9 Ω
So, the arrangement B has lower resistance.
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