Physics- General Flashcards
(47 cards)
Describe solid particles
Closely packed
Moving but joined together
What are the three states of matter?
Solid
Liquid
Gas
Describe liquid particles
Often slightly wider spaced than solids
Vibrating but NOT joined together
Slide over eachother
Describe gas particles
Very widely spaced
Able to move freely
How does a solid become a liquid?
Melting
How does a liquid become a gas?
Evaporating
Boiling
How does a gas become a liquid?
Condensing
How does a liquid become a solid?
Melting
How does a solid become a gas?
SUBLIMING
When a solid➡liquid➡gas or a solid➡gas what is required?
Energy
When a gas➡liquid➡solid, what must be released?
Energy
When particles are heated…
The volume increases
What is the effect of heating ice into water and water into steam on a balloon? What is the reason for the result?
The effect is that the balloon inflates.
This is because when the ice melted, it then evaporated and the steam rose into the balloon, making it inflate.
What is the relationship between a volume of water and the time taken for it to cool down? Why?
The relationship is that the higher volume of water the longer it takes to cool down
A smaller mass of water contains less heat energy. If energy flows out at the same time then the smaller amount of water will lose temperature faster. A small volume of water has a much higher surface area to volume ratio than a large volume. A portion of energy in a small volume of water has a much smaller distance to cover before it gets out into the air than the same portion in a large volume of water.
What is the specific heat capacity?
The energy taken to heat 1 kilogram of the material through one degree Celsius
E=mc(-). (a circle with a line in the middle)
E- energy in joules (J)
M- mass in kg
(-)- temperature rise in degrees c
C- specific heat capacity in J/kg degrees c (joules per kilogram degrees Celsius)
What equation to you use to find the specific heat capacity?
C=E
_
M (-)
What is heat transfer?
The transfer of energy from a hot body to a cold one.
What is conduction?
It is a heat transfer which occurs mostly in solids e.g heat travels from the hot end of a metal bar to the cold end
What is convection?
A heat transfer which occurs in liquids and gases e.g a portion of the liquid is heated and the hot liquid rises over the cold liquid
What is radiation?
Heat transfer by electromagnetic wave. Matt black bodies are good emitters and absorbers of thermal radiation. Shiny silver or white surfaces are poor emitters and absorbers
What is the mechanism of conduction?
When particles are heated they vibrate more. If they’re rigidly bonded then energy is easily passed between particles.
What is the mechanism for convection?
As a particle is heated it vibrates more.if it is not bonded to its neighbours it will create more room for itself. If many particles do this, they occupy more room for the same mass. The density of the fluid decreases and the hot fluid rises over th
What is the mechanism of radiation?
Atoms become excited and vibrate. As they lose energy they throw out photons, which make up light rays. Thermal radiation travels in straight lines.w
What is a cooling curve?
A graph
