### Concept Items

## 23.1 The Four Fundamental Forces

What forces does the inverse square law describe?

- the electromagnetic and weak nuclear force
- the electromagnetic force and strong nuclear force
- the electromagnetic force and gravity
- the strong nuclear force and gravity

Do the carrier particles explain the loss of mass in nuclear decay?

- no
- yes

Which of the four forces is responsible for ionic bonding?

- electromagnetic force
- gravity
- strong force
- weak nuclear force

What type of particle accelerator uses oscillating electric fields to accelerate particles around a fixed radius track?

- LINAC
- synchrotron
- SLAC
- Van de Graaff accelerator

## 23.2 Quarks

How does the charge of an individual quark determine hadron structure?

- Since the hadron must have an integral value, the individual quarks must be combined such that the average of their charges results in the value of a quark.
- Since the hadron must have an integral value, the individual atoms must be combined such that the sum of their charges is less than zero.
- The individual quarks must be combined such that the product of their charges is equal to the total charge of the hadron structure.
- Since the hadron must have an integral value of charge, the individual quarks must be combined such that the sum of their charges results in an integral value.

Why do leptons not feel the strong nuclear force?

- Gluons are the carriers of the strong nuclear force that interacts between quarks through color interactions, but leptons are constructed of quarks that do not have gluons.
- Gluons are the carriers of the strong nuclear force that interacts between quarks through mass interactions, but leptons are not constructed of quarks and are not massive.
- Gluons are the carriers of the strong nuclear force that interacts between quarks through mass interactions, but leptons are constructed of the quarks that are not massive.
- Gluons are the carriers of the strong nuclear force that interacts between quarks through color interactions, but leptons are not constructed of quarks, nor do they have color constituents.

What property commonly distinguishes antimatter from its matter analogue?

- mass
- charge
- energy
- speed

Can the Standard Model change as new information is gathered?

- yes
- no

What is the relationship between the Higgs field and the Higgs boson?

- The Higgs boson is the carrier that transfers force for the Higgs field.
- The Higgs field is the time duration over which the Higgs particles transfer force to the other particles.
- The Higgs field is the magnitude of momentum transferred by the Higgs particles to the other particles.
- The Higgs field is the magnitude of torque transfers by the Higgs particles on the other particles.

What were the original three flavors of quarks discovered?

- up, down, and charm
- up, down, and bottom
- up, down, and strange
- up, down, and top

Protons are more massive than electrons. The three quarks in the proton account for only a small amount of this mass difference. What accounts for the remaining excess mass in protons compared to electrons?

- The highly energetic gluons connecting the quarks account for the remaining excess mass in protons compared to electrons.
- The highly energetic photons connecting the quarks account for the remaining excess mass in protons compared to electrons.
- The antiparallel orientation of the quarks present in a proton accounts for the remaining excess mass in protons compared to electrons.
- The parallel orientation of the quarks present in a proton accounts for the remaining excess mass in protons compared to electrons.

## 23.3 The Unification of Forces

Why are scientists unable to model the conditions of the universe at time periods shortly after the Big Bang?

- The amount of energy necessary to replicate the Planck Epoch is too high.
- The amount of energy necessary to replicate the Planck Epoch is too low.
- The volume of setup necessary to replicate the Planck Epoch is too high.
- The volume of setup necessary to replicate the Planck Epoch is too low.

What is the name for the theory of unification of all four fundamental forces?

- the theory of everything
- the theory of energy-to-mass conversion
- the theory of relativity
- the theory of the Big Bang