Download Energy - St. John the Baptist Diocesan High School

Energy
4 Main Types
• Kinetic Energy (KE)
1. Energy of motion
• Potential Energy (PE)
1. Stored energy
• Chemical Energy
1. Energy associated with a chemical
change
4 Main Types
• Heat Energy
1.Amount of energy transferred from
one substance to another
− Can be measured using a calorimeter
− Calories (cal) or Joules (J) measure heat
gain or loss
− To convert from cal or J to kcal or kJ
divide by 1000
Law of Conservation of
Energy
• Energy is neither created nor
destroyed
1. Energy can be transferred from one
substance to another
2. Or energy can be transformed into a
new form of energy
3. THE TOTAL AMOUNT OF ENERGY
WILL REMAIN THE SAME
Law of Conservation of
Matter Continued
• Examples
1. Gas burns in engine (chem to heat)
2. Car moves (mechanical to kinetic)
Thermometry
•
Temperature
1. The measure of the average kinetic energy
of the particles of a substance
•
Heat
1. Flows spontaneously from a hot body to a
cold body
2. Examples
−
−
−
Body heat to chair
Boiling water to hand
Burned hand to icepack
Thermometry Continued
• Temperature Scales
1. Degrees Celsius (°C)
− Most commonly used scale
− Temps below zero are negative
− This scale has 2 fixed points
(0°C –melting/freezing pt. of water)
(100°C – boiling/condensation pt. of
water)
− Values on thermometer increase by 1°C
Thermometry Continued
2. Kelvin
− Contains theoretically the lowest
possible temperature 0 Kelvin (absolute
zero)
− Has never been exactly reached (1/1000
K)
− Absence of all kinetic energy (no motion
of particles)
− Scale is the same as Celsius, just shifted
by 273
− 1 degree change in Celsius is the same
as 1 degree change in Kelvin
− Table T K= °C + 273
Thermometers
Thermometers
• A device used to measure the
average kinetic energy of
particles and temperature
• Uses liquids like Hg (mercury)
and colored alcohols that
expand at high temperatures