The carbon isotope 14c is used for carbon dating of archeological artifacts. 14c(mass 2.34×10−26kg) decays by the process known as beta decay in which the nucleus emits an electron (the beta particle) and a subatomic particle called a neutrino. in one such decay, the electron and the neutrino are emitted at right angles to each other. the electron (mass 9.11×10−31kg) has a speed of 3.40×107 m/s and the neutrino has a momentum of 6.70×10−24 kg⋅m/s .
what is the recoil speed of the nucleus?
the answer is not 1900 or 1600 m/