Khan Academy on a Stick
Waves and optics

Introduction to waves
Introduction to transverse and longitudinal waves

Amplitude, period, frequency and wavelength of periodic waves
Amplitude, period, frequency and wavelength of periodic waves

Introduction to the doppler effect
Introduction to the Doppler Effect

Doppler effect formula for observed frequency
Doppler effect formula for observed frequency

Doppler effect formula when source is moving away
Doppler effect formula when source is moving away

When the source and the wave move at the same velocity
When the source and the wave move at the same velocity

Mach numbers
Mach numbers

Specular and diffuse reflection
Specular and Diffuse Reflection

Specular and diffuse reflection 2
Specular and Diffuse Reflection 2

Refraction and Snell's law
Refraction and Snell's Law

Refraction in water
Refraction in Water

Snell's law example 1
Snell's Law Example 1

Snell's law example 2
Snell's Law Example 2

Total internal reflection
Critical incident angle and total internal reflection

Virtual image
Virtual Image

Parabolic mirrors and real images
Parabolic Mirrors and Real Images

Parabolic mirrors 2
Parabolic Mirrors 2

Convex parabolic mirrors
Convex Parabolic Mirrors

Convex lenses
Convex Lenses

Convex lens examples
Convex Lens Examples

Concave lenses
Concave Lenses

Object image and focal distance relationship (proof of formula)
Object Image and Focal Distance Relationship (Proof of Formula)

Object image height and distance relationship
Object Image Height and Distance Relationship