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

Ray Diagrams and Images

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

  1. Compared to the object, how big is the image formed by a plane mirror?

    • Always smaller than the object
    • The same size as the object
    • Always larger than the object

  2. In a ray diagram for a plane mirror, is the image real or virtual?

    • Virtual image
    • Real image
    • No image forms

  3. In a plane mirror ray diagram, the image is upside down.

    Circle one:   True   False

  4. Two rays from the top of an object pass through an ideal thin converging lens and actually meet on the opposite side. What kind of image forms there?

    • A real image
    • A virtual image
    • Neither kind of image

  5. A ray parallel to the axis reaches an ideal thin converging lens in air above its centre. Where does the outgoing ray go?

    • It stays parallel and misses the far focal point
    • It bends away and misses the far focal point
    • It passes through the focal point on the far side

  6. A converging lens forms an image that is twice as tall as a 3 cm object. How tall is the image, in centimetres?

    Answer: ______________

  7. A camera lens is modelled as an ideal thin converging lens in air. A tree is well beyond twice the focal length. Which image forms on a focused sensor?

    • A virtual image, upright and larger than the tree
    • A virtual image, upright and smaller than the tree
    • A real image, inverted and smaller than the tree

  8. Mia holds a thin converging magnifying lens in air with a word inside its focal length. She describes the image as real, inverted and smaller. Which description should replace hers?

    • Real, inverted and smaller than the object
    • Virtual, upright and larger than the object
    • Real, upright and the same size as the object
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Answer key

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

Ray Diagrams and Images W1-mt_FVERuBoCD1-s1

  1. The same size as the object · A plane mirror forms an image with the same height and width as the object.
  2. Virtual image · The backward extensions of reflected rays meet behind the mirror. The reflected rays do not travel there, so the image is virtual.
  3. False · A plane mirror image is upright, so the statement is false.
  4. A real image · Rays from the same object point actually meet at its image point. This is a real image, which can form on a screen placed there.
  5. It passes through the focal point on the far side · In this lens model, a ray arriving parallel to the axis passes through the far focal point.
  6. 6 · Multiply the object height by the size factor: 3 x 2 = 6 cm.
  7. A real image, inverted and smaller than the tree · An object beyond 2f produces a real, inverted, diminished image. The focused sensor receives it at the image position.
  8. Virtual, upright and larger than the object · With the object inside the focal length, the image is virtual, upright and magnified. Mia's description gives all three properties incorrectly.
Worksheet · LightMySky