Pre Lecture
Types of energy
Energy the capacity to do work or to produce heat
PotentialEnergy Epo the energystored in an object due to its position
Epo mgh
kinetic Energy Ek the energyreleased due to motion
Ek v2
Im
Units of Energy
SI units for energy is joule CJ
2 3
lJ 1 Kg m 52 1 Pa m
Sometimes calorie is used instead of joule
1 cal 4.184 J
1cal 1000cal 1kcal
12 8 3145 Jim ol K
Important Terminology
System what is being observed
i
Surroundings i everything around the system
Universe i
everything system surroundings
Open i system can exchangeenergy r matter w the surroundings
Closed isystem can exchange energy only w surroundings
Isolated i system can't exchangematter or energy w the surroundings
Types of energy
Energy the capacity to do work or to produce heat
PotentialEnergy Epo the energystored in an object due to its position
Epo mgh
kinetic Energy Ek the energyreleased due to motion
Ek v2
Im
Units of Energy
SI units for energy is joule CJ
2 3
lJ 1 Kg m 52 1 Pa m
Sometimes calorie is used instead of joule
1 cal 4.184 J
1cal 1000cal 1kcal
12 8 3145 Jim ol K
Important Terminology
System what is being observed
i
Surroundings i everything around the system
Universe i
everything system surroundings
Open i system can exchangeenergy r matter w the surroundings
Closed isystem can exchange energy only w surroundings
Isolated i system can't exchangematter or energy w the surroundings