Ability to cause change
Different forms: Electrical, Chemical, Thermal, Radiant
What is Energy
100
Many devices convert energy from one form to another
Examples: Burning fuel in engine - kinetic energy of the car and Radiant energy - chemical energy in a plant - eat the plant - energy you use
What is changing forms of Energy
100
Measure of the average kinetic energy of the particles in an object and a unit
ºC+273=K
K-273=ºC
What is Temperature
100
Thermal energy is transferred by the collisions between particles, not by movement of matter
Best conductors of heat are metals
It happens when you touch something
What is Conduction
100
Ability to cause change
What is Energy
200
Energy of motion
Depends on Mass and Velocity
What is Kinetic Energy
200
Total potential and kinetic energy in a system
Mechanical eenrgy=KE+PE
Can transfer back and forth put the total doesn't change
What is Conversions from KE to PE
200
Sum of the kinetic and potential energy of all the particles in an object
Related to temperature, but not the same
More mass gives more thermal energy because there are more particles
What is Thermal Energy
200
Transfer of thermal energy in a fluid by the movement and cooler fluids (gas or liquid) from place to place
Warmer fluid rises because it's less dense
Convection current - rising and sinking action in a lava lamp is an example - uses both convection and conduction
What is Convection
200
Energy of motion
What is Kinetic
300
KE=1/2mv2
KE=kinetic energy (Joules)
m=mass (kg)
v=velocity (m/s)
What is Calculating KE
300
States that energy cannot be created or destroyed
Frication and air resistance - cause mechanical energy into thermal energy
Total still stays the same
What is Law of Conservation of Energy
300
Thermal energy that flows from something at a higher temperature to something at a lower temperature
What is Heat
300
Transfer of thermal energy by electromagnetic waves
Called radiant energy
Can be absorbed, reflected or transmitted
Dark colors absorb more
What is Radiation
300
Stored energy due to position
What is Potential
400
Stored energy due to position
Three types: Elastic - springs or rubber bands, Chemical - food and fuel, Gravitational - position above Earth
What is Potential Energy
400
Fusion - happens in all stars including the Sun
What is Converting Mass into Energy
400
Amount of heat is needed to raise the temperature of a 1kg of some material by 1ºC
Measured in J/(kg•ºC)
Water has a hi specific heat so takes a lot of heat to change its temperature
Metals have a low specific heat so easier to heat up and cool down
What is Specific Heat
400
Insulators - material in which heat flows slowly
wood, plastic, fiberglass and air
What is Controlling Heat Flow
400
Sum of the kinetic and potential energy of all the particles in an object
What is Thermal
500
GPE=mgh
GPE=gravitational potential energy (m/s/s) - 9.8 m/s/s
m=mass (kg)
g=acceleration due to gravity (m/s/s)
h=height above surface (m)
What is Calculating GPE
500
Measured in Calories which is really a kilocalorie
1C=4,184 Joules
1g fat=9C
1g protein or carbohydrates=4C
Body's balance: Eat=use which maintain weight, Eat>use which gain weight, Eat
What is Human Body
500
Q=m∆TC
Q=heat (J)
m=mass (kg)
∆T=change in temperature (ºC)
C=specific heat (J/kg•ºC)
Measured using a calorimeter
What is Calculating Thermal Energy
500
Atoms are made of molecules and Electrons are atoms that forces the electrons closer
What is Atoms and Electrons
500
Elastic - springs or rubber bands
Chemical - food and fuel
Gravitational - position above Earth