when water waves strike a barrier straight on, they reflect back along the same path
TRANSCRIPT
05 – THE LAW OF REFLECTION
WHAT HAPPENS WHEN WAVES HIT A BOUNDARY?
When water waves strike a barrier straight on, they reflect back along the same path.
WHAT HAPPENS WHEN WAVES HIT A BOUNDARY?
When incident waves strike a parabolic surface, the waves reflect to a focal point.
WHAT HAPPENS WHEN WAVES HIT A BOUNDARY AT AN ANGLE?
When incident waves strike a barrier at an angle they reflect off at the same angle.
The Normal (N) is a line drawn perpendicular to the barrier/surface the wave hits. The normal line intersects the surface at the identical point the wave hits the barrier/surface.
The Angle of Incidence, θi , of a wave is the angle measured from the incident wave (i) to a line normal to the barrier/surface.
The Angle of Reflection, θr , of a wave is the angle measured between the reflected wave (r) and a line normal to the barrier/surface.
THE LAW OF REFLECTION
The Angle of Incidence is equal to the Angle of Reflection
EXAMPLES
Example 1: Find the angle of reflection
ir
EXAMPLES
Example 2: Find the angle of reflection
r
EXAMPLES Example 3:
Determine which surface in the diagram the wave reflects from last and find the angle of reflection from that surface.
AB
C
D
Ei