- #1

ConnorM

- 79

- 1

## Homework Statement

- On a hot summer day, you planned a trip to a beach, but you inadvertently took a wrong turn and now you’re worried the ice in your cooler is going to melt. The cooler is 0.5 m × 0.5 m × 0.4 m, and is made with 5 cm thick Styrofoam (k = 0.033 W/m2K). Help your panicking friends by calculating the available time to find the beach before the ice melts away completely. Assume that internal convection coefficient is high enough that the inner surface of the Styrofoam matches that of the melting ice. Assume also that the temperature at the outer surface of the cooler is 10°C and the temperature of the surroundings is 35°C. Neglect any heat transfer from the bottom of the cooler (assume the cooler is resting on the foam filled seat of your car which acts as an insulator). The latent heat of fusion of the ice is 334 kJ/kg.

## Homework Equations

Basic conduction/convection equations

Q=mL

L - heat of fusion

## The Attempt at a Solution

I'm wondering how to determine the inner h value of the cooler and the outer h value in order to determine the heat transfer via convection. I'm confused as to what "Assume that internal convection coefficient is high enough that the inner surface of the Styrofoam matches that of the melting ice. " means.

Also, should a mass have been given in this problem?