1. Conservation of Energy Thermal Energy

2. Energy Elastic Energy There are a many forms of energy Electric
Energy in an object from its compression or stretching
Elastic band
Electric
The movement of electrons from 1 atom to another
Batteries
Thermal
Disorganized movement of particles in any substance
Fire
Chemical
Stored in the bonds of molecules
Combustibles
Wave
Contained in a electromagnetic wave
Radio
Hydraulic
Transported in the flow of water
Waterfall
Nuclear
Energy stored in the center (nucleus) of an atom
Sun

3. Energy Energy is defined as the capacity to do work of certain force
There are 2 types of energy
Potential (stored)
Kinetic (working)
Stored in different ways
Renewable (solar, wind, geothermal)
Nonrenewable (oil, fossil, coal)

4. Units
Energy is expressed in Joules
1 J = 1 N x 1 m

5. Law of Conservation of Energy
Energy may neither be created or destroyed, the total energy of a system remains constant
Transfer: energy from 1 place to another
Transform: energy in 1 form to another form

6. Energy Efficiency
Energy efficiency is the percentage of energy consumed by a machine or system that was transformed into useful energy.
p.72

7. Energy Output No energy is lost, but it can go unused Therefore
Net Energy = Energy(Output) – Energy(Input)
Efficiency = Input x 100
Output

8. Thermal Energy Disorganized movement of particles in a given substance
Depends on the quantity of particles and the temperature of the substance

9. Quantity of Particles
Particles Increase
Particles Decrease
Thermal Energy Increases
Thermal Energy Decrease
Temperature
Temperature Increase
Temperature Decrease

10. Heat
Heat: the transfer of thermal energy between two areas of different temperatures
Heat always passes from higher to lower
Q = ∆Et
Q = heat in J
∆Et = variation in temperature

11. Specific heat capacity
The specific heat capacity corresponds to the amount of thermal energy required to raise the temperature of one gram of substance by one degree Celsius.

12. Formula Q= heat (J) m = mass (g) C = specific heat capacity (j/g C)
Q = mc∆T
Q= heat (J)
m = mass (g)
C = specific heat capacity (j/g C)
∆T = Tf – Ti (Tf= final temp; Ti = initial temp)

13. Sample questions
Find the mass of water that released 1000J of energy by raising the temperature from 10oC to 18oC
Determine the thermal energy of 0.5 kg of water heated from 20oC to 50oC