Transfer of Heat Flashcards
define heat
it’s a spontaneous transfer of energy occurring because of a difference in temperature
It can also be said to be a form of energy that can only transfer from one point to another due to a difference in temperature
What is the SI unit for heat
Joules
What are the three main factors that determines heat transfer
Mass of the substance
change in temperature
Phase of the substance
what is the relationship between heat transfer and temperature change
Q = MC*change in temperature
Define specific heat
the amount of heat necessary to change the temperature of 1 kilogram of mass by one degrees Celsius
What is conduction
it is a heat transfer through stationary matter by physical contact
what are conductors of heat
the certain materials that allow heat to pass through them by process of conduction.
Mention three examples of conductors of heat
Metals
mercury
Alcohol
mention three examples of bad conductors of heat or heat insulators
wood
Glass
gases
Liquids
How does thermal conductivity affects conduction
So a good conductor has a high thermal conductivity and a poor conductor has a very low thermal conductivity
If the thermal conductivity is high it means that the material conduct heat easily but if a low it means the material hardly conducts heat
Explained conduction using the kinetic theory
When heat is applied to one part of a conductor, the atoms or molecules in the material become hot and energetic and begin to vibrate intensely. As they vibrate, they collide with nearby atoms and transfer some energies to them. The nearby atoms also become hot and energetic, and they also vibrate faster and also collide with other atoms and transfer their energies to them. The process goes on until heat is transferred from one atom to the last atom at the other end of the conductor until they acquire the same energy.
Can conduction take place in a vacuum true or false
false
Conduction cannot take place in a vacuum because there are no molecules or atoms in a vacuum. conduction takes place through the transfer of heat through atoms.
Define temperature gradient
this is the difference in temperature per unit length across a body.
What is the formula for temperature gradient
temperature difference divided by the distance of separation
What are the two types of heat flow
streamline heat flow
Turbulent heat flow
