Suppose that you are swimming in a river while a friend watches from the shore. in calm water, you swim at a speed of 1.25 m/s . the river has a current that runs at a speed of 1.00 m/s. note that speed is the magnitude of the velocity vector. the velocity vector tells you both how fast something is moving and in which direction it is moving. if you are swimming upstream (i. a., against the current), at what speed does your friend on the shore see you moving?

An object in mechanical equilibrium is an object

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 of the following is most likely to be the best conductor of electricity? oxygen chlorine aluminum chromium