Question1
How much 235U is consumed per year (in g/y) to produce sufficient electricity to continuously run a 100-W light bulb? How much coal (in g/y) would be essential (coal has a heat content of about 12 GJ/tom)? Assume a conversion efficiency of 33 percent of thermal energy into electrical energy.
Question2
A 0.20 kg stone is held 1.3m above the top edge of water well and then dropped into it. The well has a depth of 5.0m. Relative to the configuration with the stone at the top edge of the well, what is the gravitational potential energy of the stone-Earth System?
(a) Before the stone is released and
(b) When it reaches bottom of the well?
(c) What is the change in gravitational potential energy of system from release to reaching the bottom of the well?