AS Particle physics, units 1.0, 2.0 + 3.0

A polonium-210 nucleus is formed when a stationary nucleus of bismuth-210 decays. A beta-minus (β⁻) particle is emitted in this decay. Outline, with reference to β⁻ decay, why bismuth-210 and polonium-210 have different proton numbers.

• Bismuth-210 emits a beta-minus particle, which increases the proton number by one.

• Bismuth-210 emits a beta-minus particle, which decreases the proton number by one.

• Bismuth-210 emits a beta-minus particle, which does not change the proton number.

• Bismuth-210 emits a beta-minus particle, which doubles the proton number.

Explain how the data in Figure 1 support the hypothesis that a third particle is produced during β⁻ decay.

• The data shows a continuous energy spectrum of emitted electrons.

• The data indicates a discrete energy level for emitted electrons.

• The data supports the conservation of charge only.

• The data shows no evidence of additional particles.

The range of the electromagnetic interaction is infinite. The table below gives the range of the strong nuclear interaction and the range of the weak nuclear interaction. | Interaction | Range / m | |-----------------|-----------| | strong nuclear | 10^-15 | | weak nuclear | 10^-18 | Which particle is likely to travel the shorter distance in the tank of water before interacting?

• Positron

• Electron antineutrino

An atom of oxygen-15 \((^{15}_{8}O)\) gains two electrons to form an ion. What is the specific charge of the ion?

• -1.3 \times 10^7 \, \text{C kg}^{-1}

• -2.4 \times 10^7 \, \text{C kg}^{-1}

• -5.1 \times 10^7 \, \text{C kg}^{-1}

• -6.4 \times 10^7 \, \text{C kg}^{-1}

Which shows the classification of particles?

• A

• B

• C

• D

Calculate the speed of X. Ignore relativistic effects.

The K⁺ decays to produce an anti-muon and a muon neutrino. Which conservation law is associated with this decay?

• Conservation of energy

• Conservation of momentum

• Conservation of strangeness

• Conservation of charge

The proton number of uranium is 92 and the proton number of radon is 88. Which series of decays turns a uranium nucleus into a radon nucleus?

• α + β⁻ + β⁻ + α + α

• β⁻ + β⁻ + α + β⁻ + α

• α + α + α + α + β⁻

• β⁻ + β⁻ + β⁻ + β⁻ + α

Which row identifies particles E, F, and G?

• A. E: up quark, F: down quark, G: neutrino

• B. E: down quark, F: up quark, G: neutrino

• C. E: up quark, F: down quark, G: antineutrino

• D. E: down quark, F: up quark, G: antineutrino

A possible decay of a negative pion is π⁻ → e⁻ + Y. What is particle Y? Tick (✓) one box.

• ν̅ₑ

• νₑ

• π⁰

• 1₀n