Concave Lenses

• What is the distance from the lens to the principal focus called?

  Focal length
• What is the name of the other type of lens discussed?

  Concave lens
• How does a concave lens differ from a convex lens?

  Thicker at the edges than the center
• What happens to light rays when they hit a concave lens?

  They spread out or diverge
• What is the principal focus of a concave lens?

  It is where light rays appear to come from
• How do you draw a ray diagram for a concave lens?

  Draw a ray from the object through the center
• What are the three key properties of an image produced by a concave lens?

  Diminished, right way up, and virtual
• Why is the image produced by a concave lens considered virtual?

  Because the rays do not actually cross
• What would happen if you placed a screen where the image appears from a concave lens?

  You would not see an image on the screen
• What are the properties of an image formed by a concave lens?

  • Diminished (smaller than the object)
  • Right way up
  • Virtual (rays appear to cross)