The ceiling of your lecture hall is probably covered with acoustic tile, which has small holes separated by about 1 mm . Using light with a wavelength of 500 nm , how far L could you be from this tile and still resolve these holes

A1-lb collar is attached to a spring and slides without friction along a circular rod in a vertical plane. the spring has an undeformed length of 5 in. and a constant k =25 lb/ft. knowing that the collar is released from being held at a determine, the speed of the collar and the normal force between the collar and the rod as the collar passes through b.