P3 - Thermal Physics

Question 1

What is the simple kinetic molecular model of matter?

Answer 1

The distinguishing properties of solids, liquids and gases.

Question 2

Do solids, liquids, and gases have a definite shape?

Answer 2

Solids - yes
Liquids - no
Gases - no

Question 3

Do solids, liquids, and gases have a definite volume?

Answer 3

Solids - yes
Liquids - yes
Gases - no

Question 4

Are solids, liquids, and gases compressionable?

Answer 4

Solids - no
Liquids - no
Gases - yes

Question 5

Which states of matter flow?

Answer 5

liquids and gases.

Question 6

What are the arrangements of solids, liquids, and gases?

Answer 6

Solids - Regular, fixed, very close
Liquids - Irregular, very close
Gases - Irregular, widely separated

Question 7

What is the movement of particles in solids, liquids, and gases?

Answer 7

Solids - Only vibrates
Liquids - Free to move
Gases - Free to move

Question 8

How strong is the intermolecular force between particles in solids, liquids, and gases?

Answer 8

Solids - Very strong
Liquids - Fairly strong
Gases - Very weak

Question 9

What is gas pressure?

Answer 9

The force of the gas particles colliding with the walls of its container.

Question 10

What is Brownian motion?

Answer 10

The random motion of particles in a suspension.

Question 11

Name three differences between boiling and evaporation.

Answer 11

Boiling is fast, evaporation is slow.
Boiling takes place at a fixed temperature, evaporation can take place at various temperatures.
Boiling takes place only at the surface of the liquid, evaporation takes place throughout the liquid.

Question 12

What is the melting point of water?

Answer 12

0 Celsius

Question 13

What is the boiling point of water?

Answer 13

100 Celsius

Question 14

What is condensation?

Answer 14

The conversion of a gas into a liquid.

Question 15

What is solidification?

Answer 15

The conversion of a liquid into a solid.

Question 16

Name the four factors affecting evaporation.

Answer 16

Temperature
Surface Area
Humidity
Wind Speed

Question 17

How does an increased temperature and a constant volume affect pressure?

Answer 17

Increased pressure.

Question 18

How does a decreased volume and a decreased wall area affect pressure?

Answer 18

Increased pressure.

Question 19

What is the equation for power and volume?

Answer 19

P1V1 = P2V2

Question 20

What is the formula for pressure in terms of force and area?

Answer 20

Pressure = Force/Area

Question 21

How much do solids expand and why?

Answer 21

They expand only slightly because there are still strong bonds between the particles.

Question 22

How much do liquids expand and why?

Answer 22

They expand more than solids because the (intermolecular) bonds are weaker than in solids.

Question 23

How much do gases expand and why?

Answer 23

They expand very significantly as there are very weak bonds between particles (intermolecular).

Question 24

What does having a linear scale mean?

Answer 24

iI the scale has equal divisions (intervals) it is described as having a linear scale.

Question 25

What does sensitivity mean in a thermometer?

Answer 25

The ability of a thermometer to detect small changes in temperature.

Question 26

What does range mean in a thermometer?

Answer 26

The range of temperatures which can be measured by the thermometer.

Question 27

How does increasing the bulb size on a thermometer change its range and sensitivity?

Answer 27

Shorter range More sensitive

Question 28

How does increasing the bore diameter on a thermometer change its range and sensitivity?

Answer 28

Longer range Less sensitive

Question 29

How does increasing the stem length on a thermometer change its range and sensitivity?

Answer 29

Longer range Same sensitivity

Question 30

What is temperature?

Answer 30

The average amount of energy per particle.

Question 31

What is thermal conductivity?

Answer 31

Energy transferred per second.

Question 32

Name two good conductors.

Answer 32

Metals and graphite.

Question 33

Name two poor conductors.

Answer 33

Wood and plastic.

Question 34

Why does hot air rise?

Answer 34

It is less dense than cooler air.

Question 35

Do conduction, convection, and radiation require a medium to transfer energy?

Answer 35

Conduction - yes Convection - yes Radiation - no

Question 36

What 3 things can happen when thermal radiation falls on an object?

Answer 36

Reflect Absorb Transmit (go through)

Question 37

Good absorbers are also good...?

Answer 37

Emitters

Question 38

What color is the best emitter/absorber?

Answer 38

Matte black

Question 39

What color is the best reflector?

Answer 39

White

Question 40

What is an experiement to compare the absorption of thermal radiation on different surfaces?

Answer 40

- Place a radiant heater in the middle. - Place two different plates (e.g. black and white) on opposite sides of the heater at equal distance from the heater. - Place brass weights stuck on with wax to the backs of the plates. - See which weight falls off first