Question

Question #dfffa

Answer 1

The temperature coefficient of resistance is `5.7`x`10^(-3)` `/` `.^@"C"`.

Explanation:

The coefficient of resistance is given by the equation below:

`rArr` `R(T)=R_o[1+alpha(T-T_o)]`
where `R` is the resistance at temperature `T` and `R_o` is the resistance at temperature `T_o`. Also `'alpha'` is the coefficient of resistivity.

From above equation we can write
`rArr` `alpha = [(R/R_o)-1]xx[1/(T-T_o)]`
Considering the values as `R=5Omega,T=50^@"C"` and `R_o=7Omega,T_o=100^@"C"`, and substituting them we get,
`rArr` `alpha = [(5Omega)/(7Omega)-1]xx[1/(50^@"C"-100^@"C")]`
`=(0.71428571-1)xx(1/(-50^@"C"))`
`=(-0.2857143)xx(1/(-50^@"C"))=0.005714286/(1^@"C")`
Therefore the coefficient of resistance is `~~(5.7xx10^(-3))//.^@"C"`.