CHAPTER 32 PARTICLE PHYSICS H CHAPTER 32 EXERCISE 32B
Mass of 7 3 lithium = 7.01600 u
Mass of an alpha particle (helium nuclei) = 4.0026 u Mass of a proton = 1.672998 × 10−27 kg Mass of 234
90 thorium = 3.885124 × 10−25 kg
Mass of 238 92 uranium = 3.951643 × 10−25 kg
1. Taking 1 u = 1.66 × 10−27 kg, calculate the energy equivalent in joules and eV of 14 u.
2. If a proton in the Cockcroft and Walton experiment was accelerated by 750 keV towards the lithium target, calculate the energy released in the disintegration and write the reaction as an equation.
3. By calculating the loss in mass in the following equation, determine the energy released:
238 92 U
4 2 He + 234 90 Th
CHAPTER 32 EXERCISE 32C
Mass of a proton = 1.672998 × 10−27 kg Mass of an electron = 9.1 × 10−31 kg c = 3 × 108 m s−1; π = 2.4842 × 10–28 kg n0 = 1.674 928 6 × 10–27 kg
1. Taking the following nuclear equation for pair production, calculate the kinetic energy released for each product particle (positron and electron), if a photon of 3 × 1020 Hz is applied: hf → 2mc2 + Ek1 + Ek2.
2. Calculate the minimum frequency gamma photon that can cause pair production of an electron and positron.
3. CERN is capable of allowing multiple particles to collide head on in its particle accelerator. In the case of the following reactions, calculate the energy of each colliding proton:
p + p → π+ + π− + π− + π+ + p + p p + p → n + π− + π0 + π+ + p + p
4. Calculate the frequency of each photon produced from a pair annihilation of an electron and positron with a kinetic energy of 2 GeV each.
5. If two protons collide in a particle accelerator with a combined energy of 2.4 GeV, calculate how many pions could be produced in the reaction.
CHAPTER 32 EXERCISE 32D
1. Give an example and property of a lepton, a baryon and a meson.
2. List the six fl avours of quark and give an example of each.
3. Give the quark composition of the following particles:
(i) proton (ii) neutron (iii) positive pion
(iv) neutral kaon (v) neutral pion
4. Identify the following particles and state if they are mesons or baryons:
(i) uud (ii) dds (iii) ud (iv) udc (v) uu
5. List the fundamental forces that kaons experience.
