Question

The resistivity of manganese wire of length 1 m is 1.84 × 10-6 ohm at 20°C. If the diameter of the wire is 3 x 10-4 m, what will be the resistance of the wire at that temperature ?​

Answer 1

Given-

R = 1 m is 1.84× 10-6 ohm~ at 20 degree Celsius.

D= 3×10-4 m = 26 m

R= ?

By the Formula-

R=R.ref( 1+ Alpha+T×T.ref)

1m=R×alpha.1+20 degree Celsius×T.ref)

R= Alpha 21×20!×T.ref

R=A×210×T.ref

R=A/T.Ref+210

210/10=50

R=A.T-50

A.T/R=50

R=50-A.T.

R= -50×A.T.

NOT SURE ABOUT THIS ANSWER