physics final

the internal energy of a system can be increased by either adding heat or doing work on the system

• an ideal gas is a gas for which the forces between atoms are small enough to be ignored. 
• (Pressure x Volume)= (#gas atoms x Boltzman's constant x absolute temperature)

PV=NkT

heat is transferred by the motion of a fluid

heat is transferred by electromagnetic waves

• gasoline engine.  not all heat is used when burning
• Thermal engery- burning gas.  
• some energy converted to work
• some heat is released into enviorment 

net work done by the engy by the amount of heat used to do this work.  E= W/Qh

• efficiency.
• convert to kelvins

• ideal efficiency
• Ec= (Th-Tc)/Th

some energy is always lost 

refrigerator- cold air becoming warmer

• electric field= force vector/ charge
• units are N/C

electrostatic potential energy

electric potential

relationship between electric field and potential

• electric current
• I is electric current, q is charge, and T is time
• unit =ampere= C/s

I= V/R

unit= Omega

• E=I/R
• unit = voltage

Power supplied by the battery. 

power dissipated by a resistor

• power/time 
• kilowatt kW