1. Welcome Back Scientists! Friday, January 22, 2016 Objective: Energy Notes; I will compare the different forms of energy and the resources they come from. Homework: Vocab Quiz on Thursday, Jan 28th Agenda: 1.Questions of the Day # 1-3 2.New Vocabulary 3.Energy Notes

2. New Vocabulary ENERGY: the ability to do work or cause a change LAW OF CONSERVATION OF ENERGY: states that energy can change form but cannot be created or destroyed under ordinary conditions.

3. ENERGY NOTES

4. ENERGY OF CHANGE

5. What is Energy? Energy: The ability to cause change = work Think about things that have energy “in them”… All those things can make something DO something! It’s what causes change in everything! Nothing changes without some energy causing it. Earthquakes, Rain, even human growth is all because of energy.

6. Sun = Lots of Energy! The Sun is the source for all energy in our solar system. This is the same for all solar systems in the universe. The heat, pressure and gravity of the sun causes all energy. Energy causes change to everything!

7. Earths Interior Core Produces Energy: Radio Active Core Either it comes straight from the big bright thingy (sun), or it comes from the radioactive energy of our planet’s core. There is so much heat and pressure in the core that the Iron atoms are constantly breaking apart! This creates LOTS of heat = Energy!!!

8. There are two “types” of energy: Potential: “stored” energy (able or about to do something but isn’t just yet) The “bow” can shoot the arrow but isn’t right now. The boulder can fall but it hasn’t yet Elastic Energy is caused by changing the shape of an object (“stretching”, “bending”, “pulling”, “squishing”) Elastic Gravitational Gravitational Energy is caused by the force of gravity Pulling down on an object while the object is being held up! The ball could fall, but it hasn’t yet! There are two basic examples of Potential Energy:

9. Potential Energy The potential energy equation: PE = mass x gravity x height M = mass (in kg) G = gravity (9.8 m/s/s) H = height (in meters) PE = potential energy (in J = joules) There is an inverse relationship between potential and kinetic energy As PE increases KE decreases and as PE decreases KE increases

10. Kinetic energy: Kinetic: Energy of movement Ball falling down = Movement Movement = Kinetic Energy Gravity pulls the liquid down through the hole! This container is full of a red liquid But there is a hole! The motion of the liquid is an example of a substance with Kinetic Energy

11. Kinetic Energy The kinetic energy equation: KE = ½ mv 2 M = mass (in kg) V = velocity (in m/s) KE = kinetic energy (in J = Joules) There is a direct relationship between KE and mass and between KE and velocity squared Therefore as the mass goes up, KE goes up. And as v goes up, KE goes up.

12. Potential vs. Kinetic: The Roller Coaster has potential energy at the top of the hill But it has Kinetic energy when it rolls down the hill! The rocket has potential energy when the fuel hasn’t been lit The rocket has Kinetic energy when it’s fuel is lit and it flies through the air Wow! There’s a lot of potential energy in this sucker!

13. Main Concept 4: There are six “forms” of energy: 1) Heat Energy: (Thermal) Measurement of total movement of Particles (kinetic energy) Think: Which of the two liquid samples has a higher temperature? WHY? Liquid B Liquid A Measurement of total movement of molecules (Kinetic Energy) Heat Energy is the form of energy that is related to and caused by “heat” Heat energy is measured by “Temperature” So a higher temperature simply means that the atoms are moving faster! A higher temp. means more Kinetic energy for the molecules!

14. Heat vs. Temperature Heat = the number of molecules Temperature = the motion of molecules Which has more heat? Which has more temperature? Boiling pot of water vs. Iceberg Ice sculpture vs

15. 2) Mechanical Energy: Energy which deals with the motion of physical objects both large and small. Ball A person running… A rocket launching… Like a ball bouncing… Important: All motion will create heat! Rub your hands together, what do you feel? Run a mile, what happens to your core temp? Drive a car then feel the hood, what does it feel like? Oh! And don’t forget music!

16. Mechanical Energy The energy of an object that is due to its position (potential) or motion (kinetic). Examples: Roller coaster at top of hill PE & roller coaster going down hill KE Mechanical energy allows an object to do work! Mechanical NRG = Potential NRG + Kinetic NRG

17. Mechanical Energy Sound = Oscillations or vibrations of molecules due to compressional disturbances The wave lines represent the movement of energy! Not the movement of the molecules themselves! The little squares represent individual Molecules of a “medium”. Notice they just Move back and forth as he energy passes through!

18. Sound Energy Energy created by vibrating objects Sound travels through a medium and the speed of sound depends on the density of the medium

19. 3) Electric Energy: = Movement of electric charges in FLOW; the energy of moving electrons Lightning is Electric energy Electric energy “flows” through wires to our houses where we plug stuff in! These charges can be made to move through a wire Electricity is electric energy

20. Energy from the wave motion of a moving charged particle in the that disturbs the electromagnetic field, the result is the light we see. + /- 4) Light Energy: energy from the electromagnetic spectrum (EMS) Color is simply a form of light that our eyes can see. All forms of light are from a wave motion of particles

21. 5) Chemical Energy: Food=People Fuel! Gasoline=Car Fuel! Plants make sugar from sunlight Fire is a result of chemical energy Batteries use atomic bonds for energy 2 Oxygen atoms being held together by chemical energy! = Energy holding atoms to other atoms (“bonds”); energy stored in the Chemical compounds of food & fuel

22. 6) Nuclear energy: ■ Energy holding the nucleus (center) of an atom together. Uses atomic reactions to produce electricity. Nuclear energy holds P + and N 0 of the nucleus together If we split an atoms nucleus, we release TONS of energy!!! Examples: fission (split) and fusion (fuse) of radioactive nuclei

23. Nuclear Energy We normally think of Nuclear Energy like a nuclear bomb! The idea of this energy being let loose can be scary The most classic example of Nuclear Energy is the Sun! In fact, all the energy for every solar system starts out as Nuclear Energy in a star! But humans have figured out that we can control this energy enough to use it for electricity! Inside the sun, Atoms of Hydrogen are being broken apart and remade into new elements (like: Helium and Carbon)