Engineering Board Exam Reviewer · Voltage, Current and Resistance · medium
A copper coil has a resistance of 100, at 20° C. Find its resistance at 70° C (temperature coefficient of copper =0.00393/° C at 20° C).
- 80.35,
- 119.65,
- 19.65,
- 127.51,
Answer
B. 119.65,
Solution
R2=R1[1+ (T2-T1)]=100[1+0.00393(70-20)]=119.65, .
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