Question 1

The farthest galaxies from the Milky Way appear to be receding from us at the rate of 76,000 miles/sec. An observer in one of these distant galaxies would consider our galaxy to be
A) one of the few moving galaxies in the universe.
B) standing still at the center of the universe.
C) standing still but not at the center of the universe.
D) moving at 76,000 miles/sec and located at the center of the universe.
E) moving away at 76,000 miles/sec.

Accepted Answer

The observed recession of galaxies is due to the expansion of the universe. Therefore, an observer in another galaxy would see all galaxies, including the Milky Way, moving away from them at a rate proportional to their distance. The observed recession velocity for the Milky Way would be 76,000 miles/sec in this case. Therefore, the best choice is E, which states that an observer in a distant galaxy would see the Milky Way moving away at 76,000 miles/sec.

Question 2

One fundamental difference between a particle and its antiparticle is the
A) charge, if the particle has a charge.
B) number of quarks contained in each particle.
C) mass.
D) spin.

Accepted Answer

A particle and its antiparticle have the same mass, spin, and number of quarks, but they have opposite charges. For example, an electron has a negative charge, while its antiparticle, the positron, has a positive charge.

Question 3

The best evidence for quarks comes from
A) particles seen outside the nucleus with charge 1/3 the charge of a proton.
B) scattering experiments performed at very high energies.
C) the decay of electrons into quarks and mesons.
D) theories that would not make sense if quarks did not exist.

Accepted Answer

Scattering experiments performed at very high energies have provided the most direct evidence for quarks, by revealing the substructure of protons and neutrons in the form of three distinct point-like entities with fractional charges. This is known as "deep inelastic scattering" and was performed at accelerators such as SLAC in the 1960s and 70s.

Question 4

The result of a particle meeting its antiparticle will most likely be
A) the release of quarks contained in each particle.
B) the creation of a "black hole."
C) annihilation of the two particles and the release of photons.
D) the creation of a new particle with twice the mass of the original particles.

Accepted Answer

When a particle meets its antiparticle, they undergo annihilation and release energy in the form of photons. This is because particles and antiparticles have opposite charges and when they come together, their charges cancel out, leading to their mutual destruction. Option A is incorrect because quarks cannot be released from particles and antiparticles during their annihilation. Option B is incorrect as there is no evidence of the creation of a black hole during particle-antiparticle annihilation. Option D is incorrect because the mass of the resulting particles after annihilation is zero, and hence they cannot have twice the mass of the original particles.

Question 5

The greatest red shifts are observed for those galaxies that are
A) the brightest.
B) nearest our galaxy.
C) at the greatest distance from us.
D) near our galactic equator.

Accepted Answer

The greater the distance between two galaxies, the greater the red shift observed in the light emitted by the galaxies. Therefore, those galaxies that are at the greatest distance from us will have the greatest red shifts.

Question 6

According to current theory, which of the following elementary particles does not contain quarks?
A) Protons
B) Mesons
C) Neutrons
D) Electrons

Accepted Answer

Electrons are not made up of quarks, they are classified as leptons. Protons and neutrons are made up of quarks, and mesons are made up of a quark-antiquark pair.

Question 7

The dominant semiconducting material now in use is
A) germanium.
B) silicon.
C) carbon.
D) gallium.

Accepted Answer

Silicon is the most widely used semiconducting material in the electronics industry due to its abundance, versatility, and reliability. Germanium was used initially but has been largely replaced by silicon. Carbon and gallium are also used in certain applications, but they are not as dominant as silicon.

Question 8

Which of the following is not evidence for the Big Bang?
A) The expansion of the universe.
B) The existence of protons and neutrons.
C) The background of microwave radiation.
D) The ratio of hydrogen to helium observed in stars.

Accepted Answer

The existence of protons and neutrons is not evidence for the Big Bang. While the Big Bang theory explains how these particles were formed in the early universe, their existence alone does not serve as evidence for the theory itself. The other choices, such as the expansion of the universe, the background of microwave radiation, and the observed ratio of hydrogen to helium in stars, all provide direct evidence for the Big Bang theory.

Question 9

The oxygen atoms in Earth's atmosphere were created
A) during the Big Bang.
B) when atoms first formed, about half a million years after the beginning of the universe.
C) by nuclear fusion in massive stars.
D) during the formation of the Earth.

Accepted Answer

Oxygen atoms in Earth's atmosphere were created by nuclear fusion in massive stars.

Question 10

The term "solid-state electronics" refers to
A) the use of transistors rather than vacuum tubes.
B) the increased use of metals in electronic devices.
C) the replacement of positive charges with electrons in devices.
D) our ability to now use solids to make electronic devices.

Accepted Answer

Solid-state electronics refers to electronic circuits and devices built entirely from solid materials, where the flow of electric current is confined within solid elements. The term is often associated with the use of semiconductors, such as transistors, which replaced vacuum tubes in many applications, leading to smaller, more reliable, and energy-efficient electronic devices.

Question 11

According to the Big Bang theory, atoms would have likely begun to form after approximately
A) 10 billion years.
B) 400,000 years.
C) 1 year.
D) 3 seconds.
E) 0.5 second.

Accepted Answer

According to the current understanding of the Big Bang theory, atoms began to form approximately 400,000 years after the Big Bang, during a period called recombination. Prior to this, the universe was too hot and dense for atoms to form, as free electrons and protons were constantly colliding and ionizing each other.

Question 12

Semiconductor elements are "doped" in order to
A) increase their electrical conductivity.
B) make them less susceptible to temperature changes.
C) eliminate the possibility of incomplete bonds.
D) make them electrically charged.

Accepted Answer

Doping involves adding impurities (atoms of a different element) to a semiconductor material in order to increase its electrical conductivity. These impurities can either donate electrons (n-type doping) or create holes that can accept electrons (p-type doping) in the material, making it easier for electric current to flow through it.

Question 13

Atoms of materials that are good conductors of electricity have
A) mostly protons; thus, the negative charges jump easily from atom to atom.
B) only electrons, and so these electrons are easily moved.
C) outer electrons which are loosely bound and thus easily moved.
D) no electrons; thus, any that are given to them are easy to move about.

Accepted Answer

Materials that are good conductors of electricity have outer electrons that are loosely bound and able to move easily. This allows for the easy flow of electrons between atoms and hence make them good conductors of electricity. Choice A and D are incorrect because the presence of protons and electrons is necessary for the atom to exist and be able to conduct electricity. Choice B is incorrect because it implies that only electrons are present in conductive materials, which is not the case.

Question 14

There are several elements that we regard as semiconductors. The common property of these elements is that they have
A) electrons, which are randomly organized about the nucleus.
B) no electrons beyond a closed shell.
C) outer electrons which cannot move.
D) four outer electrons beyond a closed shell.

Accepted Answer

Semiconductors have four outer electrons beyond a closed shell, which allows for the formation of covalent bonds and the ability to conduct electricity under certain conditions.

Question 15

Which of the following fundamental forces is hardest for theorists to incorporate into an overall unified theory of nature?
A) Gravitational interaction
B) Strong interaction
C) Weak interaction
D) Electromagnetic interaction

Accepted Answer

Gravitational interaction is the hardest for theorists to incorporate into an overall unified theory of nature, primarily because it is described by the general theory of relativity, which is a classical theory, whereas the other three forces are described by quantum mechanics. Combining these fundamentally different theories into a single framework, often referred to as quantum gravity, has proven to be a significant challenge.

Question 16

The very first subatomic particle discovered was the
A) muon.
B) quark.
C) proton.
D) electron.
E) neutron.

Accepted Answer

The electron was the first subatomic particle to be discovered by J.J. Thomson in 1897 through his cathode ray experiments. The discovery of the proton came later in 1917 by Ernest Rutherford, and the neutron was discovered in 1932 by James Chadwick. The muon and quark were both discovered much later in the 20th century.

Question 17

The dominant charge carrier in a n-type semiconductor is the
A) neutron.
B) electron.
C) proton.
D) hole.

Accepted Answer

In n-type semiconductors, impurities such as phosphorus are intentionally added to provide extra electrons. These extra electrons become the dominant charge carriers, making B) electron the correct choice.

Question 18

One of the intriguing questions for scientists of many ages has been "What are the elementary particles?" Which of the following is not considered an elementary particle?
A) Quark
B) Muon
C) Proton
D) Electron

Accepted Answer

Protons are not considered elementary particles as they are composed of quarks.

Question 19

The best electrically conducting elements are located __________ in the periodic table.
A) on the left side or in the transition regions
B) in the last two columns
C) in the first two rows
D) in the middle columns
E) randomly

Accepted Answer

The best electrically conducting elements are located on the left side or in the transition regions of the periodic table because they have fewer valence electrons, which means they have a smaller number of occupied energy levels. This results in a small separation between the valence and conduction bands in the metal, allowing the electrons to move freely and conduct electricity easily.

Question 20

Which of the following is not a basic or fundamental force in nature?
A) Electromagnetic force
B) Strong nuclear force
C) Gravitational force
D) Frictional force

Accepted Answer

Frictional force is not a basic or fundamental force in nature, as it is caused by the interaction between two surfaces in contact and is dependent on various factors such as roughness, lubrication, and pressure. The other three choices (electromagnetic force, strong nuclear force, and gravitational force) are considered to be basic or fundamental forces in nature, as they are present and play a significant role in the behavior and interactions of all known matter and energy.

Quiz 21: Beyond Everyday Phenomena

The farthest galaxies from the Milky Way appear to be receding from us at the rate of 76,000 miles/sec. An observer in one of these distant galaxies would consider our galaxy to be

One fundamental difference between a particle and its antiparticle is the

The best evidence for quarks comes from

The result of a particle meeting its antiparticle will most likely be

The greatest red shifts are observed for those galaxies that are

According to current theory, which of the following elementary particles does not contain quarks?

The dominant semiconducting material now in use is

Which of the following is not evidence for the Big Bang?

The oxygen atoms in Earth's atmosphere were created

The term "solid-state electronics" refers to

According to the Big Bang theory, atoms would have likely begun to form after approximately

Semiconductor elements are "doped" in order to

Atoms of materials that are good conductors of electricity have

There are several elements that we regard as semiconductors. The common property of these elements is that they have

Which of the following fundamental forces is hardest for theorists to incorporate into an overall unified theory of nature?

The very first subatomic particle discovered was the

The dominant charge carrier in a n-type semiconductor is the

One of the intriguing questions for scientists of many ages has been "What are the elementary particles?" Which of the following is not considered an elementary particle?

The best electrically conducting elements are located __________ in the periodic table.

Which of the following is not a basic or fundamental force in nature?