Pre-Lesson

Resonance box,

Beaker, pencil, water

Refraction, reflection video

Mirror

OBJ: Given notes and activity sheet SWBAT explain the difference between reflection, refraction, diffraction and resonance with 70% accuracy.

DN: Define amplitude, wavelength and frequency.

ACT: Introduction to reflection, refraction, diffraction and resonance

Read, Text p. 17-23; Complete Interactions of Waves Booklet.

HW: Complete Interactions of Waves Booklet; Study Science Vocabulary List (SVL), define absorb-environment; WES Exam, Nov 19.

LESSON NOTES

• Reflection: wave hits a surface and bounces back; occurs in one medium only. Example: mirror

REFLECTION

LESSON NOTES

• Law of Reflection: angle of incidence equals the angle of reflection

• Incoming (Incident) ray: a wave moving toward the surface at an angle

• Reflected ray: a wave that bounces off the surface at an angle

• Normal: an imaginary line drawn perpendicular to the surface at the point where the incoming (incident) ray strikes the surface

• See transparancy

LAW OF REFLECTION

Lesson Notes

• Refraction: a wave moving from one medium into another medium changes speed causing the wave to bend; two (2) mediums. Example 1: white light breaks up into ROYGBIV by a prism.– Example 2: A rainbow is formed by refraction

of sunlight through rain droplets.– Example 3: chopstick in beaker of water

(see refraction video)

REFRACTION

REFRACTION

REFRACTION

Lesson Notes

• Diffraction: a wave moves around a corner or through a narrow opening

Lesson Notes

• Resonance: an increase in amplitude (loudness) of a vibration that occurs when external vibrations match an object’s natural frequency.

• When sound vibrates an object without touching the object.

• Example: resonance box, jet/train vibrating a window