Question 1

An anti- proton would have

Accepted Answer

A)  no charge and positive mass. 
B)  negative charge and positive mass. 
C)  negative charge and negative mass. 
D)  positive charge and positive mass. 
E)  positive charge and negative mass.

Question 2

The least massive particle of matter is now thought to be

Accepted Answer

A)  the neutron. 
B)  the neutrino. 
C)  the proton. 
D)  the photon. 
E)  the electron.

Question 3

Do neutrinos have mass, and how do we know?

Accepted Answer

A)  No, because they are observed to move at lightspeed. 
B)  No, because we have observed that their paths remain straight as they pass through a magnetic field. 
C)  Yes, because we have observed them to move slower than lightspeed. 
D)  Yes, for both of the reasons listed in answers c and d. 
E)  Yes, because we have observed them to transmute from one of the three neutrino types to another.

Question 4

How many "generations" of strongly interacting particles are there?

Accepted Answer

A)  six 
B)  four 
C)  three 
D)  two 
E)  an infinite number

Question 5

An atom of "anti- hydrogen" would be made of

Accepted Answer

A)  a high- frequency photon and a low- frequency photon. 
B)  an anti- proton and a muon. 
C)  a proton and a positron. 
D)  a positron and an electron. 
E)  an anti- proton and a positron.

Question 6

Why can we never create energy?

Accepted Answer

A)  because matter is always conserved 
B)  because energy is always conserved 
C)  because it is impossible to create the fundamental particles such as electrons and protons 
D)  because of the equivalence of mass and energy 
E)  Actually, we do create energy frequently in the lab.

Question 7

In pair creation,

Accepted Answer

A)  matter and energy are both created. 
B)  matter and energy are both conserved. 
C)  matter is conserved but energy is created. 
D)  matter is created but energy is conserved. 
E)  two oppositely- flavored pizzas are created.

Question 8

Scientists have recently discovered that

Accepted Answer

A)  it is possible for neutrinos to spontaneously transmute from one of the three neutrino types to another. 
B)  some, or possibly all, types of neutrinos have rest mass. 
C)  Both of the above. 
D)  None of the above.

Question 9

According to the standard model of fundamental particles, some of the fundamental particles form the "bricks" of the universe, while others form the "cement." Which among the following is one of the fundamental "cement" particles?

Accepted Answer

A)  positron 
B)  the proton 
C)  the Z particle 
D)  the neutrino 
E)  the quark

Question 10

Is so- called "empty" space really empty?

Accepted Answer

A)  Yes, because conservation of energy forbids the spontaneous creation of matter or radiation. 
B)  Yes, because nothing exists other than particles and empty space. 
C)  No, because all space is filled with a physical substance known as "ether." 
D)  No, because of random quantum fluctuations. 
E)  No, because neutrinos are always present at every point in the universe.

Question 11

According to the standard model of fundamental particles, some of the fundamental particles form the "bricks" of the universe, while others form the "cement." Which among the following is one of the fundamental bricks?

Accepted Answer

A)  the photon 
B)  the Z particle 
C)  the gluon 
D)  the proton 
E)  the quark

Question 12

Which of the following demonstrates the indeterminacy inherent in the microscopic [or atomic- level] world?

Accepted Answer

A)  radioactive decay 
B)  double slit experiment with electrons 
C)  Both of the above. 
D)  spontaneous creation of a positron- electron pair from a photon 
E)  All of the above.

Question 13

The Planck length is the length at which

Accepted Answer

A)  quarks are expected to be squeezed out of existence. 
B)  quantum gravitational effects are expected to become important. 
C)  electric charge becomes a meaningless concept. 
D)  strong nuclear force effects between quarks are expected to become important. 
E)  photons acquire mass and move slower than lightspeed.

Question 14

According to recent theorizing in high energy physics,

Accepted Answer

A)  it is impossible to create or destroy quarks. 
B)  we should be able to find isolated quarks. 
C)  protons and neutrons can be put together to form quarks. 
D)  All of the above. 
E)  None of the above.

Question 15

In the process of pair- creation by a high- energy photon, matter is

Accepted Answer

A)  created. 
B)  conserved. 
C)  destroyed.

Question 16

Two electrons, "A" and "B," traverse the same region of a bubble chamber. Which of the following would cause electron B's path to curve more strongly than electron A's path?

Accepted Answer

A)  Electron B has a bad cold. 
B)  Electron B has a larger mass. 
C)  Electron B is moving slower. 
D)  Electron B is moving faster. 
E)  Electron B has a larger charge.

Question 17

The positron is

Accepted Answer

A)  the anti- particle to the electron. 
B)  one of the three particles that go together to make a proton. 
C)  identical to the neutron but with a positive charge. 
D)  only hypothetical at the present time. 
E)  the anti- particle to the proton.

Question 18

Neutrinos

Accepted Answer

A)  are extremely penetrating. 
B)  move at nearly lightspeed. 
C)  have zero or near- zero rest- mass. 
D)  have all of the above properties. 
E)  have none of the above properties.

Question 19

Which one or ones of the following forces extend over macroscopic distances?

Accepted Answer

A)  the electromagnetic force 
B)  the gravitational force 
C)  Both of the above. 
D)  the strong force 
E)  all three: electromagnetic, gravitational, and strong

Question 20

According to the current theory or "standard model" of elementary particles, which one of the following is truly an "elementary" particle?

Accepted Answer

A)  electron 
B)  quark 
C)  neutrino 
D)  All of the above. 
E)  None of the above.

Exam 17: Quantum Fields: Relativity Meets the Quantum