Ray diagrams

• What type of lenses are concave lenses?

  Concave lenses are diverging lenses.
• What do concave lenses do to light rays?

  They cause the light rays to diverge and spread out.
• How are concave lenses represented in ray diagrams?

  They are represented with outward pointing V shapes at either end.
• What is the purpose of the horizontal line in a ray diagram for lenses?

  It represents the axis through the middle of the lens.
• What are the focal points in a ray diagram?

  They are points on either side of the lens where light rays converge or appear to diverge.
• What is another term for the focal point?

  The principal focus.
• What does the label '2f' represent in a ray diagram?

  It represents a point that is twice as far from the lens as the focal point.
• In a ray diagram, what is the first step when drawing the incident rays from an object?

  Pick a point near the top of the object and draw the incident rays from that point.
• What happens to the ray that passes through the center of the lens?

  It continues straight on without being refracted.
• How do we find the angle at which a ray is refracted in a ray diagram?

  By drawing a virtual ray between the point where it hits the lens and the focal point.
• What do we do after drawing all the light rays in a ray diagram?

  We find the point where the rays cross to determine the image location.
• What can we conclude about the image if the bottom of the object is on the axis?

  The bottom of the image will also be on the axis.
• What characteristics describe the image formed by a concave lens?

  The image is virtual, upright, and smaller than the object.
• What type of lenses are convex lenses?

  Convex lenses are converging lenses.
• What do convex lenses do to light rays?

  They focus light onto a single point.
• How are convex lenses represented in ray diagrams?

  They are represented with inward pointing V shapes at either end.
• What happens to the ray passing through the middle of a convex lens?

  It continues straight on without being refracted.
• What happens to the parallel ray in a convex lens ray diagram?

  It is refracted to pass through the focal point on the other side of the lens.
• How do we determine the location of the image in a convex lens ray diagram?

  By finding the spot where the refracted rays cross.
• What characteristics describe the image formed by a convex lens?

  The image is real, inverted, and smaller than the object.
• What happens to the image if the object is exactly at two times the focal distance from a convex lens?

  The image will be real, inverted, and the same size as the object.
• What happens to the image if the object is between the focal point and 2f in a convex lens ray diagram?

  The image will be real, inverted, and larger than the object.
• What happens if the object is between the focal point and the lens in a convex lens ray diagram?

  The refracted rays won't meet, and we must trace them backwards to find the image.
• What characteristics describe the image formed when the object is between the focal point and the lens in a convex lens ray diagram?

  The images will be virtual, upright, and larger than the object.
• What are the key steps to draw a ray diagram for concave lenses?

  1. Draw the concave lens with outward V shapes.
  2. Add the axis and focal points (principal focus).
  3. Draw incident rays from the object.
  4. Identify the point where the rays cross to find the image.
  5. Comment on the image characteristics (virtual, upright, smaller).
• What are the key steps to draw a ray diagram for convex lenses?

  1. Draw the convex lens with inward V shapes.
  2. Add the axis and focal points.
  3. Draw incident rays from the object.
  4. Identify the point where the rays cross to find the image.
  5. Comment on the image characteristics (real, inverted, smaller).