The Principles of Heat, Light, and Sound

Heat

Heat is transferred three ways… Conduction Convection Radiation

The first form of heat transfer is… Conduction

Conduction is heat transferred by contact. Source: Maybryonline.org

Examples…

What stops heat transfer? An Insulator.

Examples…

The second form of heat transfer is… Convection

Hot rises, cold falls creating currents. “Older Than Dirt” WebQuest Think Energy (UK)

Examples of convection

The third form of heat transfer is… Radiation

Radiation is heat as an electromagnetic wave.

The wave becomes heat when it hits an object.

Examples of radiation

Quick Review!

1. Heat is transferred through direct contact. a.Conduction b.Convection c.Radiation

2.Hot air rising, cold air falling. a.Conduction b.Convection c.Radiation

3. a.Conduction b.Convection c.Radiation

4. a.Conduction b.Convection c.Radiation

5. a.Conduction b.Convection c.Radiation

Light

Sources of light…

A light source produces light.

What happens when light hits an object? The light is reflected off the object.

We see things because of reflected light.

We see red, because red light is reflected; blue because blue is reflected; white because all light is reflected.

We see ourselves in a mirror because of reflection.

The light that hits an object is called the angle of incidence. The light that bounces off the object is called the angle of reflection.

Angle of incidence = Angle of reflection Molecular Expressions

Click here for Reflection video clip.

When light passes thru transparent objects (water, glass, etc.), the light is refracted (bent).

When light passes thru water, it’s refracted.

When light travels thru a prism, the refraction forms the spectrum. DiscoveryEducation Clipart

The spectrum is the colors of the rainbow…

Red, Orange, Yellow, Green, Blue, Indigo, and Violet (ROY G. BIV).

Click here for Rainbows and Blue Skies video clip.

Click here for Refraction Basics video clip.

Three things can happen when light hits an object.

If the object is transparent, it will pass through it.

If the object is translucent, light is diffused as it passes through it. Designbuild-Network.com

If the object is opaque, the light will not pass thru the object and is reflected.

6. We see a source of light because … a. it reflects light. b. it blocks light. c. it refracts light. d. it makes its own light.

7. A prism splits light up into its different colors. What are these called? a. The spectre b. The spectrum c. The rainbow d. The continuum

8. a. Reflectionc. Refraction b. Transparency

9. A fish tank has only one fish, but you see two fishes. This is possible because of… a. reflection.c. translucency. b. refraction.d. opaqueness.

10. From where does most of our light come? a. Electricity c. The Moon b. Light bulbs d. The Sun

Sound

Sound is caused by vibrations.

Sound moves out in every direction.

To have sound, you must have a medium.

If there is no medium, there is no sound.

Click here for Sound and Medium video clip.

A property of sound is pitch. Pitch is how high or low a sound is.

How much energy is used determines the volume (how loud) of the sound.

A lot of energy – a loud sound.

A little energy – a soft sound.

Click here for the Science of Sound.

Click here for How We Hear.

Click here for the Singing Pipe.

Click here for Reuben’s Tube.

11. Sound from a string instrument, like a guitar, are caused by… a.vibrating brass. b.vibrating lips. c.vibrating reeds. d.vibrating strings.

12. A baby hitting a pot with a spoon can hit the pot more gently and change the sound’s… a. pitch. c. tone. b. frequency. d. volume.

13. Pitch is… a. something a baseball player throws. b. closely packed molecules that carry wave patterns. c. the vibration of air molecules. d. the highness or lowness of sounds.

14. For there to be sound, it must travel through… a. plasma. b. a medium. c. solid. d. air.

15.. The harder you hit a drum… a. the louder the sound. b. the lower the pitch. c. the higher the pitch. d. the softer the sound.

11. Sound from a string instrument, like a guitar, are caused by… a.vibrating brass. b.vibrating lips. c.vibrating reeds. d.vibrating strings.

The Presentation Ends Here.