A steam pipe is covered with 1.50-cm thick insulating material of thermal conductivity of 0.200 cal/cm...

A steam pipe is covered with 1.50-cm thick insulating material of thermal conductivity of 0.200 cal/cm · °C · s. How much energy is lost every second when the steam is at 240°C and the surrounding air is at 20.0°C? The pipe has a circumference of 800 cm and a length of 50.0 m. Neglect losses through the ends of the pipe.

Expert Solution

Thickness L = 1.5 cm

Thermal conductivity K = 0.200 cal/cm · °C · s

the steam temprature t = 240°C

the surrounding air temprature t ' = 20.0°C

The pipe has a circumference = 800 cm= 8 m

length of pipe = 50.0 m

Total surface area A = circumference x length of the pipe

= 8 x 50 m ²

= 400 m ²

= 400 x 10 ⁴ cm ²

Energy is lost every second = KA(t-t')/L

= 0.2(400 x 10 ⁴ )(240-20)/1.5

= 117.33 x10 ⁶ cal / cm

genius_generous answered 1 day ago

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