The rope of a swing is 3.10 m long. Calculate the angle from the vertical at which a 76.0 kg man must begin to swing in order to have the same KE at the bottom as a 1520 kg car moving at 1.01 m/s (2.26 mph).

Hydroelectricity provides about 7 percent of the electricity generated in the united states. (a) explain how a hydroelectric power plant converts energy stored in water into electricity. (b) identify two factors that determine the amount of electricity that can be generated by an individual hydroelectricity power plant. (c) describe the two main types of land-based hydroelectric power plants. (d) describe two economic advantages and two environmental disadvantages of hydroelectricity.