Question #f83a8

1 Answer
Feb 14, 2018

The temperature difference affects the flow rate. The bigger the difference, the more is the heat flow rate.

Explanation:

Consider two long identical iron rods Rod A and Rod B. One end of each rod dips inside a bucket of ice water. (Two rods, two buckets of equal amount of ice water.)

The dry end of Rod A is heated by propane flame to become red hot, i.e., #~~1000 ^@C#. The dry end of Rod B is in room temperature. Which rod conduct more heat in the same amount of time?

The temperature difference between the two ends of Rod A is at least #(1000^@C-0^@C)#; while that of Rod B is about #25^@C# in difference. Hence the rate of heat flow is a lot higher in Rod A than Rod B despite they are identical otherwise.

Heat always flows from high temperature to low temperature. You can prove the heat flow rate is indeed depending on temperature difference by observing which rod warms up the ice water first and by how much.