Courses: P4, P14, Astr1, Astr2
Separate white light from a projector into a rainbow using a triangular prism, to show dispersion. Make sure to grab the correct prism -- it doesn't work with the other prisms in the same drawer! (Standard glass won't spread the spectrum sufficiently to see the rainbow well.) The correct prism is a high index of refraction material and can be identified by the fact that it has several chips missing -- it is extremely friable and fragile, place it down on the cart for transport, don't leave it up on the stand!
Setup: There's some fussing with focus and spread to get a really good rainbow. Plan to play with it a bit ahead of time. The slit should be at the focal point of the lens. The prism can be moved a bit side-to-side as well as forward-and-back, and rotated some, to achieve the widest dispersion while maintaining a sharp, bright rainbow. I found the 15 cm converging lens to work better than the one pictured. It might be better still to find a shorter focal length lens.
The image can be projected onto a whiteboard, or onto a white free-standing screen, depending on the arrangement of the room. Just make sure to aim the projector such that it is not facing the audience.
