The activity of an alpha-emitting source is 250 kBq250\text{ kBq}250 kBq. The kinetic energy of each alpha-particle is 4.5 MeV4.5\text{ MeV}4.5 MeV.
What is the rate of energy released by the source?
7.2×10−13 W7.2 \times 10^{-13}\text{ W}7.2×10−13 W
1.1×1012 W1.1 \times 10^{12}\text{ W}1.1×1012 W
1.8×10−7 W1.8 \times 10^{-7}\text{ W}1.8×10−7 W
1.8×10−4 W1.8 \times 10^{-4}\text{ W}1.8×10−4 W
