Convex lenses and where images form
Grade 11 Science Worksheet - Building Confidence
Circle the best answer, or write your answer on the line.
A toy 4 cm tall stands 20 cm from a convex lens, and its sharp image forms 60 cm on the other side. How tall is the image, Bo?
A toy 1.5 cm tall stands 40 cm from a convex lens, and its sharp image forms 20 cm on the other side. How tall is the image, Esme?
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Ray diagram (example data)
a convex lens with a focal length of 10 cm. A toy 2 cm tall stands 30 cm in front of it. Three principal rays leave the toy's top: one parallel to the axis bends through the far focal point; one through the lens center goes straight; one through the near focal point leaves parallel. They meet 15 cm beyond the lens, where an image 1 cm tall forms upside down.
In the ray diagram, how far from the lens does the image form, Jun?
- 30 cm, where the toy is
- 10 cm, at the focal point
- 15 cm, on the far side
In the ray diagram, which way up is the image, Kira?
- Upside down
- The right way up
- Sideways
In the ray diagram, could a screen placed 15 cm beyond the lens show the image, Luz?
- No: it is a virtual image
- Yes: it is a real image
- No: lenses don't make images
A ray from the toy travels parallel to the lens's axis. Where does it go after the lens, Milo?
- Back toward the toy
- Straight on, parallel
- Through the far focal point
A ray from the toy passes through the very center of the lens. What does it do, Noah?
- Bends through the focal point
- Reflects back
- Goes straight on without bending
A ray from the toy passes through the near focal point before the lens. How does it leave the lens, Pia?
- Through the far focal point
- Parallel to the axis
- Straight back
A magnifying glass is held so a stamp is closer to it than its focal length. What image is seen, Ren?
- Smaller, upside down and real
- Larger, upright and virtual
- The same size and real
A projector puts a small slide just beyond the lens's focal point. What image does it throw on the screen, Zee?
- Large, real and upside down
- Small, real and upright
- Virtual, so no image on the screen