Atomic and Nuclear Physics Answers

An S-wave (l = 0) resonance in the total cross section for neutrons incident on 238U is observed at a center-of-mass energy En = 115 eV. The total width of the resonance is 94 x 10-3 eV and the peak cross section is 19 200 b. Calculate the partial widths n and , for neutron and emission (assuming that these are the only final channels populated) and the peak cross section for the (n, y) capture reaction. Assume that , >n

A 100 g sample of a radioactive isotope has a half life of 2 days. After 6 days how many grams of the original radioactive isotope are left?

A radioactive nucleus of Mass M emits a photon of frequency and the nucleus recoils. The recoil will be

The pitch was clocked at 100.9 mi/hr (45.0 m/s). Determine the impulse required to give a 0.145-kg baseball such a momentum.

The mass of a typical car is m=1000kg. so its weight on the Earth’s surface is mg=9800N. Suppose you have two containers, one with N electrons and another with N protons. These two containers are placed a distance 10m apart, and the electric force between them is equal to the weight of the car. Find N.

 The mass of a typical car is m=1000kg. so its weight on the Earth’s surface is mg=9800N. Suppose you have two containers, one with N electrons and another with N protons. These two containers are placed a distance 10m apart, and the electric force between them is equal to the weight of the car. Find N.1.      

What do you think would happen to the universe that we know today if the charge of the electron becomes positive and the charge of the proton inside the nucleus becomes negative?

Tritium is an isotope of hydrogen that decays by emitting beta particles. It is used in

some luminous signs. The symbol for tritium is (3 1 H)

a. Determine the binding energy in units of MeV. Given the atomic mass of

tritium is 3.0160492 u

b. Describe three differences between an alpha particle and a beta particle.

How old is the bone if if it is presently contains 0.3125 g od C-14, but it was estimated to have originally contained 80.000 g of C-14. the half life of Carbon-14 is 5730 years.

n = ?

T = ? years

Selenium-83 has a half life of 25. 0 minutes. How many minutes would it take for a 10.0 mg sample to decay and have only 1.25 mg. remain?

n = ?

T = ? minutes