Chapter Review
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
- The rate of voltage oscillation increases as the particle travels faster and faster on each loop.
- The rate of voltage oscillation decreases as the particle travels faster and faster on each loop.
- The rate of voltage oscillation remains the same each time the particle completes a loop.
- The rate of voltage oscillation first increases and then remains constant each time the particle completes a loop.
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
- 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.
- 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 color 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
- 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
- The unification of forces will help us understand fundamental structures of the universe.
- The unification of forces will help in the proof of the graviton.
- The unification of forces will help in achieving a speed greater than the speed of light.
- The unification of forces will help in studying antimatter particles.
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.
- Proton decay is a premise of a number of GUTs.
- Proton decay negates the validity of a number of GUTs.
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
- Theory of Everything, because it requires of energy
- Theory of Everything, because it requires of energy
- Grand Unified Theory, because it requires of energy
- Grand Unified Theory, because it requires of energy
Critical Thinking Items
23.1 The Four Fundamental Forces
The gravitational force is considered a very weak force. Yet, it is strong enough to hold Earth in orbit around the Sun. Explain this apparent disparity.
- At the level of the Earth-to-Sun distance, gravity is the strongest acting force because neither the strong nor the weak nuclear force exists at this distance.
- At the level of the Earth-to-Sun distance, gravity is the strongest acting force because both the strong and the weak nuclear force is minimal at this distance.
True or False—Given that their carrier particles are massless, some may argue that the electromagnetic and gravitational forces should maintain the same value at all distances from their source. However, both forces decrease with distance at a rate of
- false
- true
- The stationary target recoils upon particle strike, thereby transferring much of the particle’s energy into its motion. As a result, a greater amount of energy goes into breaking the particle into its constituent components.
- The stationary target contains zero kinetic energy, so it requires more energy to break the particle into its constituent components.
- The stationary target contains zero potential energy, so it requires more energy to break the particle into its constituent components.
- The stationary target recoils upon particle strike, transferring much of the particle’s energy into its motion. As a result, a lesser amount of energy goes into breaking the particle into its constituent components.
- The total strong nuclear force in a lithium atom is thrice the total strong nuclear force in a lithium ion.
- The total strong nuclear force in a lithium atom is twice the total strong nuclear force in a lithium ion.
- The total strong nuclear force in a lithium atom is the same as the total strong nuclear force in a lithium ion.
- The total strong nuclear force in a lithium atom is half the total strong nuclear force in a lithium ion.
23.2 Quarks
- A particle composed of two quarks will have an integral charge and a white color. Hence, it cannot exist.
- A particle composed of two quarks will have an integral charge and a color that is not white. Hence, it cannot exist.
- A particle composed of two quarks will have a fractional charge and a white color. Hence, it cannot exist.
- A particle composed of two quarks will have a fractional charge and a color that is not white. Hence, it cannot exist.
- Mesons are composites of two antiparticles that quickly annihilate each other.
- Mesons are composites of two particles that quickly annihilate each other.
- Mesons are composites of a particle and antiparticle that quickly annihilate each other.
- Mesons are composites of two particles and one antiparticle that quickly annihilate each other.
Does antimatter have a negative mass?
- No, antimatter does not have a negative mass.
- Yes, antimatter does have a negative mass.
- During their invention, both the Standard Model and the periodic table organized material by mass.
- At the times of their invention, both the Standard Model and the periodic table organized material by charge.
- At the times of their invention, both the Standard Model and the periodic table organized material by interaction with other available particles.
- At the times of their invention, both the Standard Model and the periodic table organized material by size.
- Because some particles do not contain the Higgs boson, the collisions of such particles will cause their destruction.
- Because only the charged particles contain the Higgs boson, the collisions of such particles will cause their destruction and will expel the Higgs boson.
- Because all particles with mass contain the Higgs boson, the collisions of such particles will cause their destruction and will absorb the Higgs boson.
- Because all particles with mass contain the Higgs boson, the collisions of such particles will cause their destruction and will expel the Higgs boson.
- The combination of a quark and antiquark can result in a particle with an integer charge and color of white, therefore satisfying the properties for a hadron.
- The combination of a quark and antiquark must result in a particle with a negative charge and color of white, therefore satisfying the properties for a hadron.
- The combination of a quark and antiquark can result in a particle with an integer charge and color that is not white, therefore satisfying the properties for a hadron.
- The combination of a quark and antiquark can result in particle with a fractional charge and color that is not white, therefore satisfying the properties for a hadron.
23.3 The Unification of Forces
- Under high-energy conditions, particles interacting under the strong force will be compressed closer together. As a result, the force between them will decrease.
- Under high-energy conditions, particles interacting under the strong force will start oscillating. As a result, the force between them will increase.
- Under high-energy conditions, particles interacting under the strong force will have high velocity. As a result, the force between them will decrease.
- Under high-energy conditions, particles interacting under the strong force will start moving randomly. As a result, the force between them will decrease.
If some unknown cause of the red shift, such as light becoming tired from traveling long distances through empty space, is discovered, what effect would there be on cosmology?
- The effect would be substantial, as the Big Bang is based on the idea that the red shift is evidence that galaxies are moving toward one another.
- The effect would be substantial, as the Big Bang is based on the idea that the red shift is evidence that the galaxies are moving away from one another.
- The effect would be substantial, as the Big Bang is based on the idea that the red shift is evidence that galaxies are neither moving away from nor moving toward one another.
- The effect would be substantial, as the Big Bang is based on the idea that the red shift is evidence that galaxies are sometimes moving away from and sometimes moving toward one another.
- As energy increases, the masses of the interacting particles will increase.
- As energy increases, the masses of the interacting particles will decrease.
- As energy increases, the masses of the interacting particles will remain constant.
- As energy increases, the masses of the interacting particles starts changing (increasing or decreasing). As a result, the gravitational force between the particles will increase.
Problems
Performance Task
23.3 The Unification of Forces
Communication is an often overlooked and useful skill for a scientist, especially in a competitive field where financial resources are limited. Scientists are often required to explain their findings or the relevance of their work to agencies within the government in order to maintain funding to continue their research. Let’s say you are an ambitious young particle physicist, heading an expensive project, and you need to justify its existence to the appropriate funding agency. Write a brief paper (about one page) explaining why molecular-level structure is important in the functioning of designed materials in a specific industry.
- First, think of an industry where molecular-level structure is important.
- Research what materials are used in that industry as well as what are the desired properties of the materials.
- What molecular-level characteristics lead to what properties?
One example would be explaining how flexible but durable materials are made up of long-chained molecules and how this is useful for finding more environmentally friendly alternatives to plastics. Another example is explaining why electrically conductive materials are often made of metal and how this is useful for developing better batteries.