Drawing Ray Diagrams · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Drawing Ray Diagrams

Science · Waves, Light & Sound · ages 12-13
Name ______________________   Date ____________

  1. The angle of incidence and the angle of reflection are always equal at a flat mirror.

    Circle one:   True   False

  2. In a ray diagram, what do we call the dashed line drawn at right angles to a surface?

    • The incident ray
    • The normal
    • The reflected ray

  3. When light passes from air into glass, what happens to the ray?

    • It bends towards the normal
    • It bends away from the normal
    • It keeps going straight without bending

  4. What type of image forms behind a plane mirror, where the reflected rays only appear to meet?

    • A real image
    • A virtual image
    • A magnified image

  5. A ray hits a mirror with an angle of incidence of 28 degrees. What is the angle of reflection, in degrees?

    Answer: ______________

  6. A ray of light leaves glass and enters air. What happens to it at the boundary?

    • It bends away from the normal
    • It bends towards the normal
    • It stops travelling

  7. Jake draws a ray diagram and labels the 50-degree angle between the incident ray and the mirror's surface as the angle of incidence. Is Jake's diagram labeled correctly?

    • No, the angle of incidence should be measured from the reflected ray
    • Yes, that is the angle of incidence
    • No, the angle of incidence must be measured from the normal, not the surface

  8. A convex lens forms an image where the actual light rays cross after passing through it. What kind of image is this, and can it be projected onto a screen?

    • Real image, can be projected onto a screen
    • Virtual image, cannot be projected onto a screen
    • Real image, cannot be projected onto a screen
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Answer key

For grown-ups. Fold this page away before handing over the rest.

Drawing Ray Diagrams W1-mt_-2VNlwAR5z-s1

  1. True · That is the reflection rule: the angles, measured from the normal, always match.
  2. The normal · The normal is the reference line. You measure every angle in the diagram from it.
  3. It bends towards the normal · Glass is denser than air, so the ray bends towards the normal as it slows down.
  4. A virtual image · A plane mirror always forms a virtual image, because the rays only seem to meet behind the glass.
  5. 28 · Angle of incidence always equals angle of reflection, so the answer is 28 degrees.
  6. It bends away from the normal · Leaving a denser material for a less dense one, the ray bends away from the normal.
  7. No, the angle of incidence must be measured from the normal, not the surface · The angle of incidence is always measured between the ray and the normal. Jake measured from the surface instead, which is a common mixup.
  8. Real image, can be projected onto a screen · Because the rays truly cross, this is a real image, and real images can always be captured on a screen.
Worksheet · LightMySky