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## Homework Statement

a piece of copper wire (rho_20 = 1.7*10^-8 ohm-m) is being used as a resistance thermometer.At 20 degrees celsius, the wire is known to have a resistance of 170 ohms. when the wire is immersed in a hot oil bath, its resistance increases to 173.4 ohms. if the temperature coefficient of resistivity is 10^-3, what is the temperature of the oil?

assume that expansion of the copper negligible

## Homework Equations

current density J = nqv_d where n is electron density, q is charge, v_d is drift velocity

J = sigma*E where sigma is conductivity, E is electric field

J = E/rho where rho is resistivity

## The Attempt at a Solution

i really don't know where to start, is the 'temperature coefficient of resistivity' the same as rho?

what equation do i use that relates temperature to resistance/rho? does it have anything to do with work, as work and heat have the same unit, joules?

help appreciated..