This document discusses different types of waves including mechanical waves that require a medium and electromagnetic waves that can travel through empty space. It describes properties of waves like amplitude, wavelength, frequency, and speed. Key behaviors of waves are also outlined such as reflection, refraction, diffraction, interference, and absorption. The document provides details about electromagnetic waves, sound waves, and how lenses and mirrors interact with light waves.

1. Waves
• Wave-any disturbance that transmits
energy through matter or empty space
• Medium – substance through which a
wave can travel (solid, liquid, gas)
• Wave particles vibrate and pass the
energy to a particle next to it
• Mechanical waves must use a medium to
travel (sound, ocean waves)

2. • Electromagnetic waves travel without a
medium or in a vacuum (light waves from
the sun)
• Transverse wave-particles vibrate up and
down (wave travels forward while moving
perpendicular to the forward motion) - all
electromagnetic wave
• Longitudinal wave – moves back and
forth parallel with the direction of the
motion

3. • Compression – crowded
• Rarefaction-spread apart
• Properties of Waves :
• Amplitude-related to height, large wave
height, more energy
• Wavelength- distance between two crests
or compressions, shorter the wave length
the greater the energy

4. Frequency – number of waves in a given amount of
time, higher the frequency the greater the energy
Wave speed-the speed at which a wave travels
through a medium
Rest
position
amplitude

5. Wave Behaviors
• Reflection – wave bounces back after hitting a barrier
(sound, light, heat), at same angle
• Refraction – bending of light due to a change in medium
and a change in wave speed
• Diffraction-bending of waves around a barrier or
through an opening
• Interference – the combination of two or more waves
that results in a single wave (Ex: resonance – when two
object vibrate at the same frequency)
• Absorption: energy transferred to particles of matter

6. Electromagnetic waves
• Electric fields surround all electrically
charged objects which causes the
magnetic field to be created.
• Light travels in a straight line until it hits an
object where it can be reflected, absorbed
or transmitted
• The speed of light can change depending
on the type of media (matter traveling
through)

7. • Light is a form of radiant energy (radiation)
that moves in transverse waves
• EM energy from the sun is major source of
energy on earth
• EM spectrum consists of: left to right
• Radio waves, microwaves, infrared, visible
light, ultraviolet, x-ray, and gamma rays,
all move at the speed of light
• Energy is transferred as radiation

8. • Light travels at 300,000,000 m/s through a
vacuum and slightly less through air and
other materials
• 1 light year=9,500,000,000,000 km
(distance that light can travel in one year)

9. Sound
• Sound – energy transmitted through
matter (medium), no matter, no sound
– type: mechanical (must have matter)
– structure: longitudinal wave
• Composed of compression and rarefaction
waves (the slinky)
• Travel in all directions away from the
source
• Caused by the vibration of an object

10. EM spectrum is arranged from long wavelength to
short or from low frequency to high

11. Lenses and Mirrors
• Concave and convex lenses refract (bend)
light
• Concave – converge light (come together)
• Convex – diverge light (spread out)
• Convex mirrors - diverge light (small
upright image)
• Concave mirrors – converge light, upright
magnified image if close, inverted and
smaller if far away