Students will make a pinhole camera and be able to see the effects that light traveling in straight lines have on images.
- black construction paper
- wax paper or tracing paper
- an empty frozen juice can
- Roll the construction paper into a cone, tape the sides together, and cut the wide end of it enough so it will fit inside the juice can.
- Trace the wide circle of your cone on a the wax paper or tracing paper. Cut the circle out.
- Tape the circle to the wide end of the cone.
- Make a pinhole in the closed end of the juice can.
- Slide the cone into the open end of the juice can.
- Point the pinhole at a bright light object and look through the cone.
- Try sliding the cone in and out of the can to see a smaller and larger image.
- Try making more pinholes in the can to see multiple images of the same object.
- Have a class discussion on what the students saw on their screens and reasons why they saw what they saw.
- (Light usually travels in straight lines. If you shone a flashlight through a hole from different angles, you would see that light coming from a low angle strikes high on the surface behind the hole and vice versa. When you see an image through the hole of the camera, light reflecting off the top of the object strikes the top of the screen. That is why the image you see is upside down.)