Low-grade uranium ore contains a fraction of a percent (by weight) of uranium; very high-grade ore (as is found in some deposits in Canada) can contain up to 20% uranium. If energy is extracted from uranium by fission of 235U (0.72% of naturally occurring uranium), then how large a percentage of uranium in ore is necessary to make a tonne of uranium ore equivalent (in terms of energy) to a tonne of coal?

Place several e-field sensors at a few points on different equipotential lines, and look at the relationship between the electric field and the equipotential lines. which statement is true? 1-at any point, the electric field is perpendicular to the equipotential line at that point, and it is directed toward lines of higher voltages. 2-at any point, the electric field is perpendicular to the equipotential line at that point, and it is directed toward lines of lower voltages. 3-at any point, the electric field is parallel to the equipotential line at that point.