Unit 1 - Particles And Radiation

Question 0

What is the quark structure of a baryon? (1)

Answer 0

Three quarks

Question 1

What property defines a hadron? (1)

Answer 1

Particles that experience the strong force/interaction

Question 2

What is the quark structure of a meson? (1)

Answer 2

Quark and antiquark

Question 3

State one similarity and one difference between a particle and its antiparticle? (2)

Answer 3

Similarity - rest mass/energy

Difference - opposite charge

Question 4

State the interaction, with a reason, responsible for the decay of a K- into a negative muon and antineutrino? (2)

Answer 4

Weak interaction

Because strange not conserved

Question 5

What part of the atom is the same as a β- particle? (1)

Answer 5

Electron

Question 6

What particle is difficult to detect from β+ decay? (1)

Answer 6

Neutrino

Question 7

Give the quark structure of a neutron and proton (1)

Answer 7

Proton - uud

Neutron - ddu

Question 8

Describe how the strong nuclear force between two nucleons varies with distance, stating suitable values of desperation (3)

Answer 8

• Repulsive then attractive
• Short range
• pre 0.4fm repulsive, after attractive

Question 9

What is meant by isotopes (2)

Answer 9

• Same atomic number/proton number

* Different number of nucleons/neutrons

Question 10

State one difference between hadrons and leptons (1)

Answer 10

Leptons do not experience strong interaction, hadrons do
Or
Hadrons not fundamental, leptons are

Question 11

Hadrons can be divided into two groups. Name the groups and state a difference (3)

Answer 11

• Baryons
• Mesons
• Baryons three quarks, mesons quark and antiquark

Question 12

Which constituent of an atom has the largest specific charge? (1)

Answer 12

Electron

Question 13

Name two baryons (2)

Answer 13

Proton, neutron

Question 14

State the quark structure of the pion π+ (1)

Answer 14

Up and antidown

Question 15

Give one characteristic of a strange particle that makes it different from a particle that is not strange (1)

Answer 15

Contains strange quark
Or
Longer half life than expected
Or
Decays by weak interaction

Question 16

State what is meant by isotopes (2)

Answer 16

• Same atomic number/ number of protons

* Different mass/ nucleon number/ number of neutrons

Question 17

Explain why the alpha particle, once outside the nucleus, is unaffected by the strong nuclear force. (2)

Answer 17

• Strong nuclear force has short range

* No effect at distances larger than 3fm

Question 18

Where does the electron in pair production come from? (1)

Answer 18

Inner shell of atom

Question 19

State what is meant by specific charge and give an appropriate unit for this quantity. (2)

Answer 19

• The ratio of charge to mass

* Ckg^-1

Question 20

State the quark composition of a meson. (1)

Answer 20

Quark antiquark pair

Question 21

State the Baryon number of the K- meson. (1)

Answer 21

0

Question 22

State the quark composition of the K- meson. (1)

Answer 22

Anti up and strange quark

Question 23

What particle is responsible for the decay of a strange quark. (1)

Answer 23

Weak interaction

Question 24

What is meant by nucleon number and proton number? (1)

Answer 24

Nucleon number - number of protons and neutrons/ mass number

Proton number - number of protons/ atomic number

Question 25

State what is meant by an isotope? (2)

Answer 25

• Variations of an element that have the same proton/ atomic number
• But different nucleon number

Question 26

Explain what is meant by electron capture. (3)

Answer 26

• an atomic/orbital/shell electron
• Interacts with a proton in the nucleus via weak interaction
• Neutron formed/ up quark converted to down quark

Question 27

Name the constituent of an atom which has zero charge. (1)

Answer 27

Neutron

Question 28

Name the constituent of an atom which has the largest specific charge. (1)

Answer 28

Electron

Question 29

Name the constituent of an atom which when removed leaves a different isotope. (1)

Answer 29

Neutron

Question 30

Give two properties of hadrons that distinguish them from leptons. (3)

Answer 30

• Experience the strong interaction

* Not fundamental

Question 31

Sate one difference between the W+- boson and a photon. (1)

Answer 31

W boson charged γ not charged/ w boson has mass/ photon has infinite range