A student has 10 resistors, each of resistance r. The minimum resistance that can be obtained by him using these resistors is
Correct answer: C. r/10
- A. 10r
- B. r/100
- C. r/10
- D. r/5
Explanation
To obtain the minimum resistance, the resistors should be connected in parallel. The formula for the total resistance of resistors connected in parallel is 1/Rtotal =1/R1 +1/R2 +...+1/Rn . Substituting R1 =R2 =...=R10 =r, we get 1/Rtotal =10/r , hence Rtotal =r/10 .Incorrect options: (a), (b), and (d) These options don't correctly represent the calculation for the minimum resistance of resistors connected in parallel.
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