A ball of mass 522 g starts at rest and slides down a frictionless track, as shown below. It leaves the track horizontally, striking the ground a distance x = 0.87 m from the end of the track after falling a vertical distance h2 = 1.17 m from the end of the track. (a) At what height above the ground does the ball start to move?

(b) What is the speed of the ball when it leaves the track?

(c) What is the speed of the ball when it hits the ground?

An ionic compound can conduct electricity when a it is dissolved in water b its crystals are ground into powder c it is in solid form d it is heated to just below its melting point

People with normal vision cannot focus their eyes underwater if they aren't wearing a face mask or goggles and there is water in contact with their eyes. in a simplified model of the human eye, the aqueous and vitreous humors and the lens all have a refractive index of 1.40, and all the refraction occurs at the cornea, whose vertex is 2.60 cm from the retina.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 2.05cm in front of the eye.)

Which lists correctly orders nuclear reactions from most radioactive waste generated to least waste generated within a given period of time? o a. radioactive decay, nuclear fission, nuclear fusion o b. radioactive decay, nuclear fusion, nuclear fission o c. nuclear fusion, nuclear fission, radioactive decay o d. nuclear fission, nuclear fusion, radioactive decay