Question

At 20°C, a length of copper wire has a resistance of 10.0 Ω What is its resistance when the wire is heated to 65°C? Let α = 0.004 at 20°C. Show all work and include units of measure.

Answer 1

= 11.8 Ω

Step-by-step explanation:

Using the equation;

RT = Rr [1 + α (T -Tr)

Where;

RT = Resistance of conductor at temperature T

Rr = Resistance of conductor at reference temperature Tr

α = Temperature coefficient of resistance at reference temperature Tr

Therefore;

RT = 10 Ω [ 1 + 0.004( 65-20)]

= 10 ( 1 + 0.004(45))

= 11.8 Ω