Virtual Reflections with Pepper’s Ghost
With simple reflection off a transparent surface, you can produce virtual images that look an awful lot like Holograms.
Grades: 1 to 8
Duration: 1/2 Hour – 1 Hour
NGSS Connections PS4.B: Electromagnetic Radiation
- Plan and conduct investigations to determine the effect of placing objects made with different materials in the path of a beam of light (1-PS4-3)
- Develop and use a model to describe that waves are reflected, absorbed or transmitted through various materials (NGSS MS-PS4-2)
Step 1: Darken the room
We’re now going to create an old fashioned Pepper’s Ghost. For these activities, you’ll want to darken the room you’re working in as much as possible – the darker the room, the clearer the images!
Download the attached PDF for student worksheets and detailed information on the background and concepts for this lesson.
Step 2: Using an image
Place the printed picture on a flat surface. The surface should either be at eye level, or you should be able to crouch down so that it is.
Step 3: Reflect View
Hold the reflect view over the image at a slant. Rest the top end of the Reflect View on the table just below the picture. Make sure the beveled (stepped) edge of the Reflect View is facing towards you.
Step 4: Lazr finger
Shine the Lazr finger onto the picture. Hold it about 10-20 cm from the picture, and be careful not to shine the light through the Reflect View. you want to get as little glare as possible on the picture.
Step 5: What do you see?
Look directly into the Reflect View. you should be low enough that you don’t see the picture on the table.
What do you see? Think about how far the virtual image of the image appears to be behind the Reflect View, and how it compares to the original picture.
Step 6: Experimenting with light
Replace the picture and Lazr finger with a video played on a smart phone. Something like a candle with a black background works best.
What do you see now? Is it different than when you used the printed picture?
What could you do to make the candle appear farther away than it does now?
Use what you know about virtual images to answer these questions.