Open QuestionMeasurements on a certain isotope tell you that the decay rate decreases from 8318 decays/min to 3091 decays/min in 4.00 days. What is the half-life of this isotope?
Open QuestionThe unstable isotope 40K is used for dating rock samples. Its half-life is 1.28x10^9 y. (a) How many decays occur per second in a sample containing 1.63x10^-6 g of 40K? (b) What is the activity of the sample in curies?
Open QuestionThe common isotope of uranium, 238U, has a halflife of 4.47x10^9 years, decaying to 234Th by alpha emission. (a) What is the decay constant? (b) What mass of uranium is required for an activity of 1.00 curie? (c) How many alpha particles are emitted per second by 10.0 g of uranium?
Open QuestionRadioactive isotopes used in cancer therapy have a 'shelf-life,' like pharmaceuticals used in chemotherapy. Just after it has been manufactured in a nuclear reactor, the activity of a sample of 60Co is 5000 Ci. When its activity falls below 3500 Ci, it is considered too weak a source to use in treatment. You work in the radiology department of a large hospital. One of these 60Co sources in your inventory was manufactured on October 6, 2011. It is now April 6, 2014. Is the source still usable? The half-life of 60Co is 5.271 years.
Open QuestionWhat particle (a particle, electron, or positron) is emitted in the following radioactive decays? (a) 27 14SiS 27 13 Al; (b) 238 92U S 234 90Th; (c) 74 33As S 7434Se.
Open QuestionWhat nuclide is produced in the following radioactive decays? (a) a decay of 239 94 Pu; (b) b- decay of 24 11Na; (c) b+ decay of 15 8O.
Open Question(a) Is the decay nS p + b- + ve energetically possible? If not, explain why not. If so, calculate the total energy released. (b) Is the decay pS n + b+ + ve energetically possible? If not, explain why not. If so, calculate the total energy released.
Open QuestionThe most common isotope of uranium, 238 92U, has atomic mass 238.050788 u. Calculate (a) the mass defect; (b) the binding energy (in MeV); (c) the binding energy per nucleon.
Open QuestionHydrogen atoms are placed in an external magnetic field. The protons can make transitions between states in which the nuclear spin component is parallel and antiparallel to the field by absorbing or emitting a photon. What magnetic-field magnitude is required for this transition to be induced by photons with frequency 22.7 MHz?
Open Question(a) A high-energy beam of alpha particles collides with a stationary helium gas target. What must the total energy of a beam particle be if the available energy in the collision is 16.0 GeV?
Open QuestionThe magnetic field in a cyclotron that accelerates protons is 1.70 T. (a) How many times per second should the potential across the dees reverse? (This is twice the frequency of the circulating protons.)
Open QuestionDeuterons in a cyclotron travel in a circle with radius 32.0 cm just before emerging from the dees. The frequency of the applied alternating voltage is 9.00 MHz. Find (a) the magnetic field and
Open QuestionAn electron with a total energy of 30.0 GeV collides with a stationary positron. (a) What is the available energy?
Open QuestionA proton and an antiproton annihilate, producing two photons. Find the energy, frequency, and wavelength of each photon (a) if the p and p are initially at rest and