Cobalt-60 is a radioactive isotope that is commonly used for cancer radiation therapy. The cobalt -60 atom decays to the stable nickel-60 atom, releasing a beta particle (electron) and energy in the form of gamma rays:
If you captured the energy from the decay of a 1.25 g pellet of isotopically pure cobalt-60, how long could you run a 20.0 W light bulb?
The relevant masses are as follows.
Gamma rays are massless.
Express your answer to three significant figures and include the appropriate units.