Question

At what temperature would the resistance of a copper conductor be double its resistance at 0°C?
$\infty of \: copper = 3.9 \times 10 - 3}$
​

Answer 1

Given:

R=2R

o

α=3.9×10

−3

C

−1

ΔT=T−T

o

R

o

and T

o

are resistance and temperature at 0

∘

C

R and T are resistance and temperature at T

∘

C

R=R

o

(1+αΔT)

Substituting the given information,

2R

o

=R

o

(1+αΔT)

2=1+αΔT

1=αΔT

1=3.9×10

−3

ΔT

ΔT=256.41

∘

C

T−T

o

=T−0=T=256.41

∘

C

Hence the correct option is (A).