Question

A long wire of diameter d = 1cm is submerged in an oil bath of temperature t∞ = 25oc. the temperature of the wire at time t = 0 is ti = 100oc. if the convection coefficient is h = 500 w/m2-k, how long does it take for the wire to reach a temperature that is within 1oc of the steady state value

Answer 1

KNOWN: Diameter, resistance and current flow for a wire. Convection coefficient and temperature

of surrounding oil.

FIND: Steady-state temperature of the wire. Time for the wire temperature to come within 1℃ of it’s

steady-state value.

SCHEMATIC: