Energy The ability to bring about change or do work. Energy Transformation: Change from one type of energy to another. Energy Transfer When a certain form of energy moves to another object.

Kinetic Energy: Potential Energy: Energy an object has due to its motion. Energy that is stored in an object. Roller Coaster Showing potential and kinetic energy transformation

Which point(s) will have the maximum potential energy? Which point(s) will have the least potential energy? Which point(s) will have the maximum kinetic energy? Which point(s) will have both kinetic and potential energy? A C and then E A B D E B and D C A

Gravitational Potential Energy Is a type of potential energy considering the and objects _______ and _______. Which skier has more GPE? Why? The more mass = More or Less GPE The more distance = More or Less GPE mass height I have more GPE because we have the same mass, but I am at a greater height! You are correct I am lower!

Temperature Is the measure of the average kinetic energy (energy of motion) or average speed of all the particles in a material. Higher temperature = particles move faster and farther apart Lower temperature = particles move slower and closer together Which water is hotter? Hotter water particles moving faster and farther apart; blue dye spread out quickly Cooler water particles moving slower and close together; take longer for blue dye to spread

An object does not “have” heat Is the transfer of energy from a place with higher temperature to a place of lower temperature. Heat

Thermal Energy Thermal energy is the energy a substance or system has related to its temperature, i.e., the energy of moving or vibrating molecules. Atoms and molecules, the smallest particles of any substance, are always in motion. The motion of thermal energy is usually not visible, but we can feel or see its effects. We use thermal energy to cook our food and heat our homes, and we use it to generate electricity. Total kinetic energy of all the particles in a material More molecules = more thermal energy Almost always released (not lost or destroyed) during an energy transformation- felt has heat

Can you have the same temperature water but have different amounts of thermal energy? YES more atoms, more thermal energy less atoms, less thermal energy

Law of Conservation of Energy The total amount of energy before something happens must be equal to the amount afterward Energy can be transferred or transformed but can not be created or destroyed Total energy does not change True or False: A friend tells you that a generator “makes” electricity.

Energy Efficiency No energy transformation results in 100% useful energy Ratio of useful energy to that is released to the total energy used Example: Gas in car 74% of energy released as heat 26% of energy is transformed into motion Engines efficiency= 26%

Since energy is never created or destroyed – follow energy transfer Energy Types

Transfer of Energy Using the table on the previous page, decide the type of energy at each of the situations.

Conduction Transfer of Energy When two objects touch each other and transfer energy from the hotter one to the colder one - gases, solids, liquids – due to the collision of atoms and molecules. Conductor Materials that allow energy to transfer easily.

Insulators Less collision of atoms and molecules When conduction is slowed down, insulation occurs. Gases poor conductors (vacuum)

Results Final temperature 40 0 C Temperature Change 60 0 C C 20 O C + 20 O C Final temperature 48 0 C Temperature Change 60 0 C C 20 O C + 28 O C Final temperature 34 Temperature Change 60 0 C C 20 O C + 14 O C

Calculating Energy Lost Energy released (calories) = Temperature change of water (c) X Mass of water (g) Energy unit of measurement One calorie is the amount of energy required to raise 1 gram of water 1 C Calorie joule, BTU (1 cal = 4.2 joules) How to Calculate Calories 1 mL of water weighs 1 gram Food Calories: Calorie (capital C) = 1000 calories

Measuring Calories In Food Mass of 1 cheese ball1.2 g Volume of water100mL Initial temperature of water20 O C Final temperature of water36 O C According to the results, how many calories in a cheese ball? And in a serving? Calories = Change temp. X Mass water 21 O C x 100g = 2,100 calories Convert to food Calories divide by 1,000 = 2.1 Calories per cheese ball 2.1 Calories per cheese ball 32 cheese balls per serving 2.1 X 32 = 67.2 Calories/serving The nutrition information on the cheese ball bag states 32 cheese balls contain 150 Calories. Propose several reasons why the value you calculated is lower than the energy actually stored in a cheese ball.

Continuing supply supplied faster than it is used up! Limited supply once it is used up there is no more of it! Renewable Resources Nonrenewable Resources Wind Energy Geothermal EnergyBiomass Energy Tidal HarnessSolar Energy Nuclear Energy Fossil Fuels (coal, petroleum, natural gas) Renewable and Nonrenewable Resources Hydroelectric Energy

Which Energy Sources are considered renewable? Which Energy Sources are considered nonrenewable? Fossil Fuels (coal, petroleum, natural gas) Nuclear Energy Biomass Geothermal Hydroelectric Solar Tidal Harness Wind Energy Energy Sources

Battery Chemical energy to electrical energy to - mechanical, light, etc (potential) (kinetic) Electrolyte - material capable of conducting electricity that allows the current to flow as it is released from the reaction. How does a battery work video Electrons flow from negative to positive

Copper Positive terminal least active gain electrons Magnesium Negative terminal most active gives up electrons _ _ _ _ _ _ _ _ _ _ _ Electrolyte _ _ _ _ _ _ _ KEY Electrons Flow of electricity How a Battery Works _ _

Negative terminal give up electrons Positive terminal gain electrons According to the charts, which metal would you pair with Lithium to make a strong battery? Explain your choice Lithium should be paired with Gold to produce the most energy releasing battery. Lithium is most active thus making it want to give up electrons. Gold is least active thus making it want to gain electrons. This movement of electrons makes electricity.

Energy and Magnetic Fields Electromagnetism Video Earth’s geographic north pole is Earth’s magnetic south pole. Earth is a gigantic magnet

Electrical Circuits Predict if the following materials conduct electricity! MaterialConducts Electricity Aluminum Copper Glass rod Carbon rod Wood Zinc Granite Plastic Ceramic tile Magnesium Iron yes no

Parallel and Series Circuit Does the diagram represent a parallel or series circuit? What happens if you unscrew one of the light bulbs? All the lights will go out since there will be a break in the circuit. The flow of electricity will stop and not be able to complete the circuit. Does the diagram represent a parallel or series circuit? What happens if you unscrew one of the light bulbs? All the lights will stay on since there will not be a break in the circuit. The flow of electricity will continue and complete the circuit.

Lightbulb Efficiency Are lightbulbs better at producing light or heat? Which is the best lightbulb? Use evidence from the chart.