A uranium nucleus \({ }^{238} \mathrm{U}\) at rest decays to a thorium nucleus \({ }^{234} \mathrm{Th}\) by emitting an alpha particle (which is a helium nucleus \({ }^{4} \mathrm{He}\) ):

The mass of the uranium atom is \(m_{\mathrm{U}}=395.292632 \times\) \(10^{-27} \mathrm{~kg}\), the mass of the thorium atom is \(m_{\mathrm{Th}}=\) \(388.638541 \times 10^{-27} \mathrm{~kg}\), and the mass of the helium atom is \(m_{\mathrm{He}}=6.646479 \times 10^{-27} \mathrm{~kg}\). What is the combined kinetic energy of the fragments?

Transcribed Image Text:

238U-234Th + He.