Conservation Laws & Particle Interactions (AQA A Level Physics)

Which diagram represents the process of beta-minus decay?

The decay of a  kaon is given by the equation

What are particles X and Y?

Which row in the table, A to D, does not give the correct exchange particle for the process described?

Which row, A to D in the table, does not show the correct interactions experienced by the type of particle?

The decay of a  baryon is given by the equation

Which row, A to D in the table, correctly identifies the charge, baryon number and lepton number of particle X?

This Feynman diagram shows particles interacting via a W^– boson. Which of the following particle choices are correct?

Complete the following β⁺ decay.

Four possible combinations of quarks are shown. Which ones have the same charge?

The decay of a muon is given by the equation

Which row correctly identifies the charge, baryon number and lepton number of particle X?

Which row, A to D in the table, does not give the correct exchange particle for the process described?

Up quarks have a charge of  while down quarks have a charge of .

Which of the following combinations of three quarks must make up a neutron?

In positron emission an up quark is changed to a down quark.

The following decay equation for this is incorrect.

Which row correctly describes the checking a student would do to find the error?

The following Feynman diagram shows the baryons and leptons in a nuclear decay

Which of the four Feynman diagrams, A to D, is physically equivalent to the diagram given for this decay?

The graph shows an isotope of uranium (U) with its corresponding nucleon and proton numbers.

This isotope of uranium decays by alpha emission to become thorium (Th), which then undergoes β-decay to become protactinium (Pa), which undergoes a further β-decay to become a different isotope of uranium.

How does the quark composition of the nucleus change in the conversion of thorium to uranium?

Equation 1 shows the decay of a proton p, and equation 2 shows the decay of a Xi baryon, Ξ⁰.

Neither of the two decay equations are permitted. For each one, identify which properties are not conserved.

Equation 1: 

Equation 2: 

Which of the following processes and Feynman diagrams, A to D, correspond to the following decay equation?

A particle is found to be affected by both the electromagnetic force and the strong force.

Which one of the following could it be?

A proton decays into a neutron, a positron, and a neutrino, as shown.

It cannot decay into a neutron and a neutrino without the emission of the positron.

Which of the following conservation laws would not be conserved if it did?

1. charge

2. lepton number

3. strangeness

4. baryon number

Equation 1 shows the decay of a neutron, and Equation 2 shows the decay of a Sigma baryon.

Neither of the two decay equations are permitted. For each one, identify which property is not conserved.

Equation 1: 

Equation 2: