The resistance of a metal rod at $20^{\circ }$C is $5.0,\Omega$. Its temperature coefficient of resistance is $0.004,\text{per}{;}^{\circ }$C. What is its resistance at $80^{\circ }$C?

Step-by-step solution

1. 1. Calculate temperature change: $DeltaT=80-20=60^{c}irc$C.
2. 2. Use $R=R_0[1+alphaDeltaT]$ with $R_0=5.0,Omega$, $alpha=0.004$.
3. 3. Compute $R=5.0[1+0.004\times 60]=5.0[1+0.24]=5.0\times 1.24=6.2,\Omega$.
4. 4. The answer is $6.2,Omega$.

Concept tested: Temperature dependence of resistance

Published 4 September 2026 · Last updated 16 September 2026 · How this solution was prepared and checked