wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

The resistance of wire at 20C is 20Ω, and at 300C resistance of wire is 50Ω. The temperature at which its resistance will be 40Ω is

A
100C
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
107C
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
207C
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
200C
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is C 207C
R=R0{1+αΔθ}
So,
20=R0{1+α.20}
50=R0{1+α.300}
25=1+20α1+300α2+600α=5+100α
500α=3
α=6×103
Hence,
R=R0{1+αΔθ}
50=R0{1+6×103×300}
=R0=502.8

R=502.8{1+6×103×Δθ}
40=502.8{1+6×103×Δθ}
Δθ=206.670C which is close to 2070C.

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Dependence of Resistance on Temperature
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon