2. Thermal Physics Flashcards
Describe liquid
Weaker attractive force than solid
No fixed pattern
Particles slide past each other
Describe solid
Strong forces of attraction between particles
Have fixed pattern
Atoms vibrate but can’t change position
Describe gas
Almost no intermolecular force
Particles are far apart, move quickly
Gases spread out to fill up the container and exert equal pressure on all surfaces
Collide with each other and bounce in all direction
What is pressure of gas
Due to particles colliding on the container wall
Describe brownian motion
Smoke particles appear to be in random motion
This is bc they are constantly being hit by other rapidly moving particles in the air
This is a evidence that particles in air are in constant random motion
Massive particles may be moved by light, fast moving particles
Describe evaporation
The transformation of liquid into a gas at a temperature below the boiling point of the liquid
Particles with more kinetic energy move faster and overcome the force of attraction between the molecules and escape from the surface
Constantly occur on the surface of the liquid
Relate evaporation to cooling
More energetic particles escape, the liquid contains fewer high energy particles and more lower energy particles so the average temperature decrease
Describe the factors affecting evaporation
More surface area, higher temperature and blow air across the surface increase evaporation
Describe Boyle’s law
When temperature is constant, pressure x volume = constant
Describe the the al expansion of liquid gas and solid
Liquid expand -> increase volume
Gas expand at constant volume -> higher pressure, at constant pressure -> higher volume
Gas > liquid > solid
What is fixed point
Use to define a scale of temperature
Fix points are definite temperature at which sth happen
Ice point : 0c - pure ice melt
Steam point : 100c pure water boil
What is thermometric property of the thermometer
The physical property that varies with temperature
Describe the liquid in glass thermometer
Consists of a thin glass bulb joined to a capillary tube
The liquid fills the bulb and the tube
When the bulb become warmer, liquid expand and the liquid in the bulb is forced into the capillary tube
The amount of expansion can be matched to a temperature on the scale
Use in home, office, greenhouse and hospital
What is range
The lowest and highest temperature of the thermometer
What is sensitivity
The extent of change in the thermometric property for a 1c rise of temperature
