The largest blocks in the Great Pyramid weigh 15 tons (about 13,600 kg). Dragging such a block up a ramp with a mechanical advantage of 3 would
require a force of 4.5 104 N. If 9.0 105 J of work was done on the block to
move it up the ramp, neglecting friction, how far was the block moved?

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.