1. Energy Notes 2

2. Heat
Heat also called infrared (I.R.) radiation
Longer wavelength than light!
Heat is energy measured in joules
A heat SOURCE contains more heat than a heat SINK and is higher temperature!
Heat moves from source to sink!

3. Temperature
Measures the average kinetic energy of the molecules of a substance
More heat = higher temperature
Thermometers use 3 scales to measure temperature:
Celsius (C)
Fahrenheit (F)
Kelvin (K)

4. Temperature Scales ESRT p 13

5. Specific Heat
Amount of heat needed to be absorbed by a substance to raise its temp. 1oC
High specific heat = substance warms up s-l-o-w-l-y….
Low specific heat= substance warms up quickly!
A good absorber is a good radiator
ESRT p. 1: Charts to answer questions…

6. Phase Changes
Solid to liquid= melting
Liquid to vapor (gas) = vaporization
The substance GAINS HEAT with both!
Vapor  liquid = condensation
Liquid  solid = freezing/solidification
The substance LOSES HEAT with both!
Condensation Video
Phase Changes Video

7. Check the box which describes whether energy
is gained or lost for each process.
Process
Energy Gained
Energy Lost
Condensation
Evaporation
Melting
Solidification

8. Water warms very slowly compared to other natural substances. Why?
Heat Summary
Water warms very slowly compared to other natural substances. Why?
HIGH specific heat
Does water also COOL slowly? Why?
Poor absorber = poor radiator
Sand/soil warms up quickly! Why?
LOW spec. heat, rough texture, dark color
Does the sand/soil COOL quickly?
Good absorber = good radiator
Where at the beach is it warmer when the sun is out? At night?