Series Combination Of Resistors

Resistors connected end to end carry the same current, and their equivalent resistance is the simple sum of the individual values, expressed as $R_{eq}=R_1+R_2+R_3$, a rule set out in NCERT Class 12, Chapter 3 (Current Electricity). Adding the given resistors, $R_{eq}=2+3+5=10$ ohm. In a series arrangement the total opposition always exceeds the largest single resistor because the current must pass through every element in turn. The option 0.968 ohm results from mistakenly applying the reciprocal parallel formula $\frac{1}{R_{eq}}=\frac{1}{2}+\frac{1}{3}+\frac{1}{5}$. The option 30 ohm comes from wrongly multiplying the three values together. The option 3.33 ohm is merely the arithmetic average, which has no physical basis for a series network. A magnitude check confirms the result: the series total of 10 ohm is larger than the biggest component (5 ohm), exactly as expected when resistances add up along a single path.