Each a particle in a beam of a particles has a kinetic energy of 4.5 MeV. Through what potential difference would you have to accelerate these a particles in order that they would have enough energy so that if one is fired head-on at a gold nucleus it could reach a point 1.9 10^-14 m from the center of the nucleus?

An atom in an excited state has a mass of 63.332 and then decays to a mass of 63.329 amu by emitting 3 x-rays of equal energy. a) What is the energy (in keV) and wavelength of each x-ray? b) If one of these X-rays is absorbed by a neighbouring atom and ejects a K-shell electron, what is the velocity of the electron? (note: K-shell binding energy is 43 keV)

In a Rutherford scattering experiment, an a-particle (charge = +2e) heads directly toward a gold nucleus (charge = +79e). The α-particle had a kinetic energy of 5.0 MeV when very far (r→ ∞) from the nucleus. Assuming the gold nucleus to be fixed in space, determine the distance of closest approach. Hint: Use conservation of energy with PE =kq1q2/r.

K:43) Assuming only maximum energy transfers occur for 12C ions with electrons in a material, determine the number of collisions required for a 100 MeV 12C ion to go to energy below 10 MeV.

Calculate the equivalent energy of one atom of beryllium (9.0 amu) in joules, using the conversion factors of 1 amu = 931.5 MeV and 6.25 x 10¹8 eV = 1 joule.

3. A beam of helium-3 atoms (m = 3.016 u) is incident on a target of nitrogen-14 atoms (m = 14.003 u) at rest. Dur- ing the collision, a proton from the helium-3 nucleus passes to the nitrogen nucleus, so that following the col- lision there are two atoms: an atom of "heavy hydro- gen" (deuterium, m = 2.014 u) and an atom of oxygen-15 15.003 u). The incident helium atoms are moving at (m a velocity of 6.346 × 10° m/s. After the collision, the deu- terium atoms are observed to be moving forward (in the same direction as the initial helium atoms) with a velocity of 1.531 x 10' m/s. (a) What is the final velocity of the oxygen-15 atoms? (b) Compare the total kinetic energies before and after the collision.

A uranium nucleus  238U (initially at rest) decays into a thorium nucleus 234Th and an alpha particle. Which one has the greater velocity?   the 234Th nucleus   the alpha particle   Both the same

How much work (in eV) does it take to move 12 protons though a 4V potential difference?

A positron and an electron with negligible kinetic energy meet and annihilate one another, producing two y-rays of equal energy. the wavelength of these y-rays is ..···. O 2.428 pm O 14.28 Á O 4.822 pm O 1.428 pm

Assume a hypothetical atom with a nucleus that consists of two positrons (instead of two protons). Positron has a charge of +1 and the mass of an electron. Write down the hydrogen like energy of a neutral 2-positrons atom.