heat and temperature Flashcards
Define heat
energy transfer due to a temperature difference
Define thermal equilibrium
When 2 objects are at the same temperature therefore heating doesn’t occur
2 objects are in thermal equilibrium when…
+ Heating doesn’t occur
+ they are both at the same temperature
what are the 2 types of heating?
+ Heating by particles
+ Heating by radiation
describe heating by particles (3 MARKS)
When energy is transferred from objects with particles moving at higher average speeds to an object with particles moving at lower average speeds. Due to the particles randomly colliding
The different average speeds of the particles are due to…
The different average speeds of the particles of 2 objects are due to their different temperatures.
describe heating by radiation
When energy is transferred by electromagnetic radiation from an object at a higher temperature, to an object at a lower temperature
compare kinetic energy between a hot block and cold block.
And explain why that’s the case. (3 MARKS)
On average, the particles in the hot block have more kinetic energy than the particles in the cold block.
because the particles in the hot block are vibrating at a higher speed than the particles in a cold block.
describe how energy transfers between a hot and cold block when touching. (6 MARKS)
assuming the 2 blocks are perfectly insulated.
when the hot block and cold block touch, the particles between them are colliding.
Motion is transferred with every collision.
Therefore the average kinetic energy in the hot block decreases and…
The average kinetic energy in the cold block increases
until the particles in both blocks have the same kinetic energy.
NOTE: The particles will still continue to collide, but the average kinetic energy in each box will REMAIN CONSTANT
what happens when a block is heated up?
When a block is heated up, the average kinetic energy of the particles increases
Define temperature
a measure of the average kinetic energy of particles
(that make up a solid, liquid and gas)
what happens when a gas cools down?
The average kinetic energy of the particles decreases, along with a decrease in temperature
at 0 degrees Celsius…
ice cubes melt (melting point)
state the SI units used for temperature
Kelvin
at 100 degrees Celsius
Water boils (boiling point)
