Unit 6: Topic 3 - Heat Transfer and Thermal Equilibrium

Question 1

How do the particles in a warm body compare to those in a cooler body?

Answer 1

The particles in a warmer body have a greater average kinetic energy than those in a cooler body. This is because kinetic energy and temperature are proportional.

Question 2

What is heat transfer?

Answer 2

When there is a heat transfer, heat flows from the warmer object to the cooler object. Heat transfer occurs through the collisions of particles until the system is at thermal equilibrium.

Question 3

What is thermal equilibrium?

Answer 3

Thermal equilibrium is achieved as the particles of different temperature continue to collide. Thermal equilibrium is when the kinetic energies of the two particles are the same, meaning the temperature is as well. Here is a diagram.

Question 4

Here is the diagram for this question. A) What is the change in temperature for the metal?
B) What time is thermal equilibrium achieved?
C) Does the average speed of the metal particles increase or decrease with time?

Answer 4

A) Around -62.5 C. Final temp is 37.5 and the initial temp is 100. 37.5-100= -62.5
B) Thermal equilibrium is achieved around 120 seconds because the temperature has stopped changing.
C) The average speed of the metal particles decreases because the temperature decreases meaning that the average kinetic energy of the particles decreases as well.