Exam 2 topics

Center of gravity - balanced torques (T = F L, on both sides of "lever"), what makes things stable  (C/G must be supported)

Energy
Waves
- wavelength
- frequency
- speed
- amplitude
- crests and troughs

wave speed = frequency x wavelength
(Note that the wave speed is the speed of light when you are talking about electromagnetic waves.)

mechanical vs. electromagnetic waves

music - octaves (doubling the frequency); the next note on the piano (1.0594)

Doppler effect
- red shift, blue shift

electromagnetic spectrum - radio, micro, IR, visible (ROYGBV), UV, X, gamma

light reflection

light refraction

lenses and mirrors (convex and concave)

focal length/point

predicting light paths (when light is reflected or refracted)

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