A long stainless steel tool bar of 20 mm ¥ 20 mm cross-section is perfectly insulated on three sides and is maintained at a temperature of 400°C on the remaining side. Determine the maximum...

A long stainless steel tool bar of 20 mm ¥ 20 mm cross-section is perfectly insulated on three sides and is maintained at a temperature of 400°C on the remaining side. Determine the maximum temperature in the bar when it is conducting a current of 1000 A. The thermal and electrical conductivity of stainless steel may be taken as 16 W/m K and 1.5
 10⁴
( cm)^–1
and the heat flow at the ends may be neglected.