Reflection Physics Example 2

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Example 2

medium
A light ray strikes a mirror. The angle between the incident ray and the reflected ray is 80°80°. What is the angle of incidence?

Solution

  1. 1
    The incident and reflected rays make equal angles with the normal.
  2. 2
    So the angle between the two rays is 2θi2\theta_i.
  3. 3
    2θi=80°  ⟹  θi=40°2\theta_i = 80° \implies \theta_i = 40°

Answer

θi=40°\theta_i = 40°
The total angle between incident and reflected rays is twice the angle of incidence. This geometry follows directly from the law of reflection.

About Reflection

The change in direction of a wave at a boundary so that it returns into the original medium.

Learn more about Reflection →

More Reflection Examples

Example 1 easy

A light ray hits a plane mirror at an angle of [formula] to the normal. What is the angle of reflect

Example 3 easy

A ray of light hits a smooth surface at an angle of [formula] to the normal (perpendicular). What ha

Example 4 medium

A concave mirror has a focal length of [formula]. An object is placed [formula] from the mirror. Use

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