The resistance of a platinum wire at `0^@ C` is ` 4 Omega`. What will be the resistance of the wire at `100^@ C` if the temperature coefficient of resistance of platinum is `0.0038 //^@ C`.

Explanation

The resistance of a platinum wire at `0^@ C`
`R_0 = 4 Omega`
Temperature coefficient of resistance
`alpha = 0.0038//^@ C`
Resistance at `100^@ C` is
`R_(100) = R_t = R_0 (1 + alpha t)`
`R_t = 4 [ 1 + 0.0038 xx 100]`
` = 4 (1 + 0.38)`
` = 4 xx 1.38 = 5.52 Omega`
Resistance at `100^@ C` is `R_(100) = 5.52 Omega`.