An electric wire of resistance 50 ohm is cut into five equal wires. These wires are then connected in parallel. What is the equivalent resistance of this combination?
[amp_mcq option1=”2 ohm” option2=”10 ohm” option3=”0.5 ohm” option4=”5 ohm” correct=”option1″]
This question was previously asked in
UPSC NDA-1 – 2022
The resistance of a uniform wire is directly proportional to its length. So, if the wire is cut into five equal parts, the resistance of each part is R’ = R/5 = 50 ohm / 5 = 10 ohm. When n equal resistors (each of resistance r) are connected in parallel, the equivalent resistance (Req) is given by Req = r/n. In this case, r = 10 ohm and n = 5. Thus, Req = 10 ohm / 5 = 2 ohm.