P3 - Thermal Physics Flashcards
What is the simple kinetic molecular model of matter?
The distinguishing properties of solids, liquids and gases.
Do solids, liquids, and gases have a definite shape?
Solids - yes
Liquids - no
Gases - no
Do solids, liquids, and gases have a definite volume?
Solids - yes
Liquids - yes
Gases - no
Are solids, liquids, and gases compressionable?
Solids - no
Liquids - no
Gases - yes
Which states of matter flow?
liquids and gases.
What are the arrangements of solids, liquids, and gases?
Solids - Regular, fixed, very close
Liquids - Irregular, very close
Gases - Irregular, widely separated
What is the movement of particles in solids, liquids, and gases?
Solids - Only vibrates
Liquids - Free to move
Gases - Free to move
How strong is the intermolecular force between particles in solids, liquids, and gases?
Solids - Very strong
Liquids - Fairly strong
Gases - Very weak
What is gas pressure?
The force of the gas particles colliding with the walls of its container.
What is Brownian motion?
The random motion of particles in a suspension.
Name three differences between boiling and evaporation.
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.
What is the melting point of water?
0 Celsius
What is the boiling point of water?
100 Celsius
What is condensation?
The conversion of a gas into a liquid.
What is solidification?
The conversion of a liquid into a solid.
Name the four factors affecting evaporation.
Temperature
Surface Area
Humidity
Wind Speed
How does an increased temperature and a constant volume affect pressure?
Increased pressure.
How does a decreased volume and a decreased wall area affect pressure?
Increased pressure.
What is the equation for power and volume?
P1V1 = P2V2
What is the formula for pressure in terms of force and area?
Pressure = Force/Area
How much do solids expand and why?
They expand only slightly because there are still strong bonds between the particles.
How much do liquids expand and why?
They expand more than solids because the (intermolecular) bonds are weaker than in solids.
How much do gases expand and why?
They expand very significantly as there are very weak bonds between particles (intermolecular).
What does having a linear scale mean?
iI the scale has equal divisions (intervals) it is described as having a linear scale.
What does sensitivity mean in a thermometer?
The ability of a thermometer to detect small changes in temperature.
What does range mean in a thermometer?
The range of temperatures which can be measured by the thermometer.
How does increasing the bulb size on a thermometer change its range and sensitivity?
Shorter range
More sensitive
How does increasing the bore diameter on a thermometer change its range and sensitivity?
Longer range
Less sensitive
How does increasing the stem length on a thermometer change its range and sensitivity?
Longer range
Same sensitivity
What is temperature?
The average amount of energy per particle.
What is thermal conductivity?
Energy transferred per second.
Name two good conductors.
Metals and graphite.
Name two poor conductors.
Wood and plastic.
Why does hot air rise?
It is less dense than cooler air.
Do conduction, convection, and radiation require a medium to transfer energy?
Conduction - yes
Convection - yes
Radiation - no
What 3 things can happen when thermal radiation falls on an object?
Reflect
Absorb
Transmit (go through)
Good absorbers are also good…?
Emitters
What color is the best emitter/absorber?
Matte black
What color is the best reflector?
White
What is an experiement to compare the absorption of thermal radiation on different surfaces?
- 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
