In the autocollimation experiment of sec. 3.5, a thin convex lens is placed 25 cm from a pinhole that acts as a point source of light. a plane mirror placed 20 cm behind the lens reflects the light back through the lens, and the reflected light forms a sharp spot beside the pinhole. what is the focal length of the lens (in cm)?

What is the scientific definition of energy that relates to work

The necleus of an atom is made up of what subatomic particles?

With the simplified model of the eye, what corrective lens (specified by focal length as measured in air) would be needed to enable a person underwater to focus an infinitely distant object? (be careful-the focal length of a lens underwater is not the same as in air! assume that the corrective lens has a refractive index of 1.62 and that the lens is used in eyeglasses, not goggles, so there is water on both sides of the lens. assume that the eyeglasses are 1.90