Reflection and Refraction Bouncing Wave The medium for
Reflection and Refraction
Bouncing Wave ] The medium for waves is not always uniform. • Extreme case is for a collision with a barrier A single pulse is reflected back in the opposite direction.
Open Ended ] The medium may end in air. • Extreme case the end is loose and completely free A single pulse is reflected back in the same direction.
Mixed Media ] The medium may change. • A thin rope attached to a thick rope Part of the pulse is reflected but part is transmitted.
Ray Tracing ] Waves can be seen as sets of parallel lines moving forward. • Wave fronts • May be curved ] A ray follows a point of successive wave crests. • Perpendicular to front • Straight until a barrier is reached
Perfect Mirror ] Larger waves also interact with barriers. We can follow a line perpendicular to the wave front. • These are called rays ] A reflected ray has the same angle after reflection. • Angle qi = qr
Rough Shoulder ] A car approaches a sandy shoulder from pavement. • The wheels that hit the shoulder slow down • An angle causes the car to turn into the shoulder
Refraction ] As a wave changes its medium the speed changes, and so does its wavelength.
Snell’s Law ] ] For plane waves the angles are related to the speeds in the two media. This is called Snell’s Law next
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