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A roller coaster at an amusement park has a dip that bottoms out in a vertical circle of radius r. A passenger feels the seat of the car pushing upward on her with a force equal to twice her weight as she goes through the dip. If r = 15.5 m, how fast is the roller coaster traveling at the bottom of the dip? Number i Units
A space laboratory is rotating to create artificial gravity, as the figure indicates. Its period of rotation is chosen so that the outer ring (ro = 2060 m) simulates the acceleration due to gravity on earth (9.80 m/s2). What should be the radius r₁ of the inner ring, so it simulates the acceleration due to gravity on the surface of Mars (3.72 m/s²)? Number i Units <>
A 78.0-kg man is riding an escalator in a shopping mall. The escalator moves the man at a constant velocity from ground level to the floor above, a vertical height of 5.00 m. What is the work done on the man by (a) the gravitational force and (b) the escalator? (a) Number (b) Number p. i Units Units