On a winter day with a temperature -10C, it is observed that the lake has a 1cm thick layer of ice over the entire surface. Assuming the temperature stays constant, find how long it will take for the ice to be safe:

(a) If the air temperature remains at -10C, find the rate in cm per hour at which ice is added to the layer. The thermal conductivity of ice is 2.18W/m · K.
(b) Find the time that the ice layer reaches a thickness of 20 cm.

Question

On a winter day with a temperature  -10 C, it is observed that the lake has a 1cm thick layer of ice over the entire surface. Assuming the temperature stays constant, find how long it will take for the ice to be safe:

(a) If the air temperature remains at  -10 C, find the rate in cm per hour at which ice is added to the layer. The thermal conductivity of ice is 2.18W/m · K.
(b) Find the time that the ice layer reaches a thickness of 20 cm.