If a 4. 5 kg object is dropped from a height of 6. 0 m, what will be its velocity when it is halfway toward the ground? (Use g = 9. 80 m/s2, and ignore air resistance. ) 7. 7 m/s 11 m/s 16 m/s 29 m/s.

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