Deck 26: Quarks, Leptons, and the Big Bang

Question 1

An example of a fermion is a:

A) photon
B) pion
C) neutrino
D) kaon
E) none of these

Answer 1

neutrino

Question 2

An example of a boson is a:

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

Answer 2

photon

Question 3

A particle can decay to particles with greater rest mass:

A) only if antiparticles are produced
B) only if photons are also produced
C) only if neutrinos are also produced
D) only if the original particle has kinetic energy
E) never

Answer 3

never

Question 4

All leptons interact with each other via the:

A) strong force
B) weak force
C) electromagnetic force
D) strange force
E) none of these

Question 5

The stability of the proton is predicted by the laws of conservation of energy and conservation of:

A) momentum
B) angular momentum
C) baryon number
D) lepton number
E) strangeness

Question 6

When a kaon decays via the strong interaction the products must include a:

A) baryon
B) lepton
C) strange particle
D) electron
E) neutrino

Question 7

Strangeness is conserved in:

A) all particle decays
B) no particle decays
C) all weak particle decays
D) all strong particle decays
E) some strong particle decays

Question 8

Two particles interact to produce only photons, with the original particles disappearing. The particles must have been:

A) mesons
B) strange particles
C) strongly interacting
D) leptons
E) a particle, antiparticle pair

Question 9

Two baryons interact to produce pions only, the original baryons disappearing. One of the baryons must have been:

A) a proton
B) an omega minus
C) a sigma
D) an antiparticle
E) none of these

Question 10

The baryon number of a quark is:

A) 0
B) 1/2
C) 1/3
D) 2/3
E) 1

Question 11

Quarks are the constituents of:

A) all particles
B) all leptons
C) all strongly interacting particles
D) only strange particles
E) only mesons

Question 12

Any meson is a combination of:

A) three quarks
B) two quarks and an antiquark
C) one quark and two antiquarks
D) one quark and one antiquark
E) two quarks

Question 13

Any baryon is a combination of:

A) three quarks
B) two quarks and an antiquark
C) one quark and two antiquarks
D) one quark and one antiquark
E) two quarks

Question 14

The quark content of a proton is:

A) uuu
B) uud
C) udd
D) ddd
E) uds

Question 15

The quark content of a $\pi$ ⁺ meson is:

A) uu
B)
C) ud
D)
E)

Question 16

The two basic interactions that have finite ranges are:

A) electromagnetic and gravitational
B) electromagnetic and strong
C) electromagnetic and weak
D) gravitational and weak
E) weak and strong

Question 17

Messenger particles of the electromagnetic interaction are called:

A) gluons
B) photons
C) W and Z
D) gravitons
E) pions

Question 18

Messenger particles of the strong interaction are called:

A) gluons
B) photons
C) W and Z
D) gravitons
E) pions

Question 19

Messenger particles of the weak interaction are called:

A) gluons
B) photons
C) W and Z
D) gravitons
E) pions

Question 20

A down quark can be changed into an up quark (plus other particles perhaps) by:

A) the gravitational interaction
B) the electromagnetic interaction
C) the weak interaction
D) the strong interaction
E) none of these

Question 21

The color theory explains why quarks:

A) form particles in pairs and triplets
B) have charge that is a multiple of e/3
C) have spin
D) have mass
E) none of the above

Question 22

Color is carried by:

A) only quarks
B) only leptons
C) only quarks and leptons
D) only quarks and gluons
E) only photons and gluons

Question 23

Hubble's law is evidence that:

A) the speed of light is increasing
B) the universe is expanding
C) the Earth is slowing down in its orbit
D) galaxies have rotational motion
E) none of the above

Question 24

As a result of the big bang there is, in addition to the microwave background radiation, a uniform distribution of background:

A) electrons
B) quarks
C) gluons
D) neutrinos
E) atoms

Question 25

The velocities of distant objects in the universe indicate that the time elapsed since the big bang is about:

A) 10⁵ y
B) 10¹⁰ y
C) 10¹⁵ y
D) 10²⁰ y
E) 10²⁵ y