Radium–226 decays by alpha emission to radon–222, which in turn decays by alpha emission to polonium–218. The half-life of Radium–226 is 1620 years while the halflife of radon–222 is 3.83 days. (a). What is the equilibrium ratio of the number of Radium–226 nuclei? (b) How much time was initially required to establish that equilibrium?

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.