Physics 2 Quiz 1

temperature

how fast on average the molecules are moving

how does speed of molecules relate to temperature?

higher speed=higher temp

if there are 2 different systems with different amounts of molecules but the molecules are going the same speed, how does this affect the temperature and thermal energy of the systems?

• temperature: stays the same

• thermal energy: higher in system with more molecules

how does mass of molecules affect thermal energy?

larger molecules means there is more thermal energy

thermal energy

total sum of energy of molecules in a system due to random movement

how is heat transferred from one object to another?

energy is transferred from hot object to cold object

is energy transferred between molecules with the same velocity?

no

is energy transferred betwen molecules with different velocities?

yes

1st law of thermodynamics

• energy is conserved

• 2 ways to change thermal energy in a system: work and heat

• ΔEth= Q+W

how can thermal energy be lowered?

• the system does work on the environment

• the system gives Q (heat) to the environment