Chapter 14 Changing Forms of Energy Energy Energy

Chapter 14 Changing Forms of Energy

Energy • Energy- the ability to do work or cause a change • It can change an objects motion, color, shape, temperature, or other qualities • It cannot be created or destroyed, but can be transferred to other objects

Examples of Energy Transfer • A lamp changes electrical energy into light energy • Gasoline releases a chemical energy that moves a car • Other kinds of energy: Sound, light, electricity, magnetism, chemical, nuclear, mechanical, thermal

Kinetic and Potential Energy • Kinetic: Energy due to motion • Potential: Energy that is not causing any changes now, but could cause changes in the future • Read pages 448451

http: //www. youtube. com/watch? v=T 5 WJoup-RD 8

Potential and Kinetic Energy • Potential – Water behind a dam – Battery • Kinetic – Water moving across turbine blades

A cute picture!

4 Main Types of Energy • • Chemical Energy Heat Energy Light Energy Mechanical Energy

Chemical Energy • A kind of potential energy • Energy caused by chemical reactions • Examples: – Cooking food – Burning something – Batteries – Matches

Mechanical Energy • Mechanical energy is matter in motion. • An airplane soaring through the sky has mechanical energy just like the wind or a flowing river. • Sound is another type of mechanical energy. • Other examples: compressed springs, stretched rubber bands, bow and arrow, hammer and nail

Thermal (Heat) Energy • The total of all the kinetic and potential energy of the atoms in an object • When any forms of matter gets warmer, the object’s thermal energy increases

Thermal (Heat) Energy • Energy pushed into motion by heat • Examples: – Insulation – Refrigerators – Air conditioners – The Sun – Stove

Conduction, Convection, and Radiation • Read page 465 in your book

Conduction • The flow of heat between objects that are touching

Convection • The movement of warm liquids or gases to cooler areas

Convection

Radiation • The movement of energy by electromagnetic waves

Light Energy • Travels in waves • It is Electromagnetic Radiation – a combination of electrical and magnetic energy • Look at the pictures on page 458 & 459

Light Energy • Light energy comes from the Sun. Plants use it to make food and scientists use it to create lasers. • Examples: – Light bulb – Fire – The Sun – Flashlight – Firefly/Lightning bug

Let’s look at how lenses can bend light!

Concave and Convex Lenses

Concave Lens • Light is bent outward • Makes objects look smaller

Convex Lens • Bends light rays to make objects look larger • Thickest in the middle • Magnifying glass is one example

Here’s a short word from our friend, Bill! • http: //www. youtube. com/watch? v=f. D 1544 b. M_c 4

Major Parts of the Eye

Light Moving Through the Eye https: //www. youtube. com/watch? v=sya. Qgmxb 5 i 0

Light and Color • http: //www. youtube. com/watch? v=AD 1 Xic 2 mn 0 U

Let your brain rest while you look at this adorable walrus!

http: //studyjams. scholastic. com/studyjams/science/matter/energy-andmatter. htm

Energy • http: //www. youtube. com/watch? v=bt. LU 2 lb 3 -xs

Sound Energy • Sound is a wave of vibrations that spreads from its source • Frequency- how fast particles are vibrating • Read page 454 and 455 to yourself • How does your ear work? – http: //www. youtube. com/watch? v=HMXo. HKw Wm. U 8

Sound Energy http: //www. youtube. com/watch? v=l. Tetdgpu 7 MU

Now, Let’s Look at a Cute Picture!