Resistance of the wire is measured as 2 Ω and 3 Ω at 10 ° C and 30 ° C respectively. Temperature coefficient of resistance of the material of the wire is

Step-by-step solution

Resistance of a material is related to temperature by expression R = R 0 1 + α Δ T Here, at 10 ° C , we have 2 = R 0 1 + 10 α       . . . i And at 30 ° C , we have 3 = R 0 1 + 30 α         . . . i i From equation i , R 0 = 2 1 + 10 α   Putting this value in equation i i , 3 = 2 1 + 10 α 1 + 30 α ⇒ 3 + 30 α = 2 + 60 α ⇒ 1 = 30 α Hence, temperature coefficient of the material of wire is α = 1 30 = 0 .