Thermal Physics

Question 1

How do you find the Kelvin temperature?

Answer 1

Celsius temperature + 273

Question 2

What are the postulates of the Kinetic Molecular Theory of Matter?

Answer 2

1. Matter is composed of tiny particles
2. These particles are in constant, random motion and possess kinetic energy
3. The particles also have potential energy due to intermolecular attractions
4. The average kinetic energy increases as the temperature increases
5. Energy is transferred from one particle to another during collisions, but at constant temperature the total energy of the system is constant

Question 3

What is thermal energy?

Answer 3

The internal energy present in a system due to its temperature; transfer of thermal energy when heating or cooling a substance

Question 4

What is temperature?

Answer 4

The degree or intensity of heat present in a substance or object, expressed according to a comparative scale

Question 5

What is kinetic energy?

Answer 5

The motion of particles in a substance.

Question 6

What is heat?

Answer 6

The energy transferred from one system to another because of a difference in temperature.

Question 7

What is internal energy?

Answer 7

The total potential and kinetic energy o the particles in a system.

Question 8

What is absolute zero?

Answer 8

The lowest temperature that is theoretically possible, at which the motion of particles which constitutes heat would be minimal.

Question 9

Conduction

Answer 9

Transfer of heat takes place under direct contact with no net movement of particles.

Question 10

Convection

Answer 10

The process of heat transfer from hot body to cold body by the bulk movement of the molecules within fluids such as gases and liquids.

Question 11

Radiation

Answer 11

Energy that comes from a source and travels through space at the speed of light with no movement of matter and without visceral contact.

Question 12

Conductors

Answer 12

Material that allow electricity or thermal energy to pass through easily.

Question 13

Insulators

Answer 13

Materials that do not allow electricity or thermal energy to pass through.

Question 14

Thermal Conductivity

Answer 14

The ability of a material to conduct heat, measured in watts per metre kelvin.

Question 15

Specific heat capacity

Answer 15

The amount of thermal energy required to raise the temperature of 1kg of a substance by 1 degree.

Question 16

Latent heat

Answer 16

Heat required for an object to change phase (melt, boil, freeze, etc.)

Question 17

Why does steam burn more than water?

Answer 17

Steam has more heat energy than water due to its latent heat of vaporisation and additionally latent heat of condensation.

Question 18

Thermal Equilibrium

Answer 18

The condition of a system in which there is no net exchange of thermal energy between any of its components

Question 19

Zeroth law of thermodynamics

Answer 19

The transfer of energy from a system with higher temperature to a system with lower temperature until thermal equilibrium is reached.

Question 20

Conservation of Energy

Answer 20

Energy cannot be created or destroyed; it simply changes form.