The slope of a line on a distance-time graph represents . distance time displacement speed

Work out sian speed for the first 30 minutes of her journey. give your answer in km/h.

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

Why is the energy that results from a roller coaster's position at the top of a hill referred to as potential energy?