Nuclear Physics

How Joseph John Thomson Discovered the Electron

• studies light rays in vacuum tubes- and rays traveled from anode to cathode

• studied light rays in vacuum tubes- and rays traveled from cathode to anode

• studied cathode rays in vacuum tubes- rays traveled from anode to cathode

• studied cathode rays in vacuum tubes- rays traveled from cathode to anode

• studied cathode rays in vacuum tubes- rays traveled from cathode to anode

What did Joseph John Thomson observe?

• observed that rays were reflected by electric and magnetic fields

• observed that lights were reflected by electric and magnetic fields

• observed that rays were deflected by electric and magnetic fields

• observed that lights were deflected by electric and magnetic fields

• observed that rays were deflected by electric and magnetic fields

What was the conclusion of Jospeh John Thomson ?

• concluded that light carried negative charge, electrons

• concluded that light carried positive charge, protons

• concluded that rays carried negative charge, electrons

• concluded that rays carried positive charge, protons

• concluded that rays carried negative charge, electrons

Ernest Rutherfords discovery of the nucleus, was found from what experiment and led to what conclusion?

• the experiment was aiming a beam of beta particles at a thin silver foil. Led to the conclusion that atoms have a non-heavy nucleus that occupies a very tiny volume within the whole atom

• the experiment was aiming a beam of beta particles at a thin gold foil. Led to the conclusion that atoms have a heavy nucleus that occupies a very tiny volume within the whole atom

• the experiment was aiming a beam of alpha particles at a thin silver foil. Led to the conclusion that atoms have a non-heavy nucleus that occupies a very tiny volume within the whole atom

• the experiment was aiming a beam of alpha particles at a thin gold foil. Led to the conclusion that atoms have a heavy nucleus that occupies a very tiny volume within the whole atom

• the experiment was aiming a beam of alpha particles at a thin gold foil. Led to the conclusion that atoms have a heavy nucleus that occupies a very tiny volume within the whole atom

Chadwicks Discovery of what ?

• proton

• neutron

• electron

• particles

• neutron

What was the experiment conducted by James Chadwick and what was the conclusion?

• the experiment was in 1932, James Chadwick bombared beryllium with beta particles, since the radiation couldnt be explained by gamma rays due to its mass and momentum, he concluded it was neutrons

• the experiment was in 1932, James Chadwick bombared beryllium with alpha particles, since the radiation couldnt be explained by gamma rays due to its mass and momentum, he concluded it was neutrons

• the experiment was in 1932, James Chadwick bombared beryllium with beta particles, since the radiation couldnt be explained by gamma rays due to its mass and momentum, he concluded it was electrons

• the experiment was in 1932, James Chadwick bombared beryllium with alpha particles, since the radiation couldnt be explained by gamma rays due to its mass and momentum, he concluded it was electrons

The cross sectional area of nuclei can be determined from particle scattering experiments

• true

• false

• true

What is (in)stability in nuclear physics?

• For subatomic particles, stability often relates to the particle’s tendency to decay into other particles. Particles like electrons, protons, and neutrons are considered stable because they have extremely long lifetimes, with no evidence of decay under normal conditions.

• For atomic particles, stability often relates to the particle’s tendency to decay into other particles. Particles like electrons, protons, and neutrons are considered stable because they have extremely long lifetimes, with no evidence of decay under normal conditions.

• For subatomic particles, stability often relates to the particle’s tendency to decay into other particles. Particles like electrons, protons, and neutrons are considered less stable because they have extremely long lifetimes, with no evidence of decay under normal conditions.

• For atomic particles, stability often relates to the particle’s tendency to decay into other particles. Particles like electrons, protons, and neutrons are considered less stable because they have extremely long lifetimes, with no evidence of decay under normal conditions.

• For subatomic particles, stability often relates to the particle’s tendency to decay into other particles. Particles like electrons, protons, and neutrons are considered stable because they have extremely long lifetimes, with no evidence of decay under normal conditions.

Isotopes, in the neutral state have:

• equal number of protons, equal number of electrons

• different number of protons, different number of electrons

• equal number of protons, equal number of electrons

Isotopes, not in the neutral state have:

• equal number of protons, equal number of electrons

• different number of protons, different number of electrons

• equal number of protons, equal number of electrons

what is the method used to determine the age of organic materials using carbon radioactive

• radiocarbon dating

• carbon-14-dating

• carbon dating

• old dating machine

• more than one are correct

• more than one are correct

• radiocarbon dating

• carbon-14-dating

How does radiocarbon dating work ?

• By measuring the amount of carbon-14 remaining in the sample and comparing it to the amount of carbon-14 present in the atmosphere at the time the organism died one can calculate the approximate age of the sample.

• By measuring the amount of carbon-16 remaining in the sample and comparing it to the amount of carbon-14 present in the atmosphere at the time the organism died one can calculate the approximate age of the sample.

• By measuring the amount of carbon-16 remaining in the sample and comparing it to the amount of carbon-16 present in the atmosphere at the time the organism died one can calculate the approximate age of the sample.

• By measuring the amount of carbon-20 remaining in the sample and comparing it to the amount of carbon-20 present in the atmosphere at the time the organism died one can calculate the approximate age of the sample.

• By measuring the amount of carbon-14 remaining in the sample and comparing it to the amount of carbon-14 present in the atmosphere at the time the organism died one can calculate the approximate age of the sample.

two neutrons and one proton, which elements of the nuclei belong to?

• tritium

• helium

• water

• air

• tritium

two protons and one neutron, which elements of these nuclei belong to?

• tritium

• helium

• water

• air

• helium

Fewer than ___ of the known nuclei are stable (not radioactive)

• 20%

• 5%

• 50%

• 10%

• 10%

Stable nuclei cluster __ to the curve called the line of stability

• higher

• lower

• very close

• very far

• very close

there are no stable nuclei with Z…?

• Z>82

• Z<82

• Z>80

• Z<80

• Z>82

The force that holds the nucleons together is called the strong force.

1. it is an ___ force between any two nucleons

• repulsive

• attractive

• attractive

The force that holds the nucleons together is called the strong force.

1. it does not on __________

• protons

• electrons

• neutrons

• electrons

The force that holds the nucleons together is called the strong force.

1. it is a _____ range force, acting only over nuclear distances

• long

• short

• medium

• constant

• short

The force that holds the nucleons together is called the strong force.

1. Over the range where it acts, it is ____ than the electrostatic force that tries to push two protons apart.

• stronger

• weaker

• neutral

• stronger

What the difference in potential energy of two nucleons versus. electrostatic potential energy of two protons

• the strong force has vanished by r~ 3fm

• the maximum force occurs at r ~ 1.5 fm where the slope is the maximum

• the maximum force have vanished by 2fm

• more than one are correct

• the strong force has vanished by r~ 3fm

• the maximum force have vanished by 2fm

what balances the repulsive coulomb force?

• attractive “strong interaction”

• weak “interactions”

• attractive “ energy interactions”

• weak “energy interactions”

• attractive “strong interaction”

strong interactions only work where?

• long range

• short range

• “surface” of the nuclei

• “center” of the nuclei

• “center” of the nuclei

In large nuclei which interaction wins

• coulomb interaction

• strong interaction

• weak interaction

• “surface” interaction

• coulomb interaction

The mass of the nucleus is the same as the sum of the mass of its nucleons

• true

• false

• true

• LESS

A nucleus is a bound system. Energy is required to disperse the nucleons by breaking the nuclear bonds between them

• binding energy

• healthy energy

• collapsing energy

• strong energy

• binding energy

the most stable elments of the universe are at the ____ energy part of the graph

• lowest

• highest

• medium

• center

• highest

As heavy elements decay into lighter ones, they approach a highly stable state, resulting in a massive release of energy, this is

• fussion

• explosions

• fission

• collapse

• fission

As light nuclei merge, they form heavier ones, also approaching a highly stable state, resulting in a massive energy release, called

• thermonuclear fusion

• fission

• vision

• nothing

• thermonuclear fusion

What is the most stable element of the universe

• Fe(56)

• He(4)

• Kr(89)

• Ba(144)

• Fe(56)

The product of the uncertainty in the position and the uncertainty in the momentum of a particle is greater than or equal to a constant value.

• energy time uncertainty principle

• angular momentum uncertainty principle

• position momentum uncertainty principle

• position momentum uncertainty principle

Relates the uncertainty in the energy of a system to the uncertainty in the time over which the energy is measured.

• energy time uncertainty principle

• angular momentum uncertainty principle

• position momentum uncertainty principle

• energy time uncertainty principle

For a particle with angular momentum L about a particular axis, the product of the uncertainty in angular momentum and the uncertainty in the angular position is greater than or equal to a constant.

• energy time uncertainty principle

• angular momentum uncertainty principle

• position momentum uncertainty principle

• angular momentum uncertainty principl

quantum tunneling allows particles to pass through barriers that are not allowed in

• classical physics

• normal physics

• microscopic physics

• macroscopic physics

• classical physics

Quantum tunneling follows both from the ___ and from ___

• uncertainty principle, Schrondingers equation

• classical principle, Schrondingers equation

• uncertainty principle, Einsteins equation

• classical principle, Einsteins equation

• uncertainty principle, Schrondingers equation

Quantum tunneling has reduced probability but NOT

• reduced energy

• increased energy

• partical energy

• wave energy

• reduced energy

In classical physics can particle be in the middle barrier

• yes, it can be on the right side, left and middle barrier

• no, only in the left or right barrier

• no, only in the left or right barrier

In quantum physics can the particle be in the middle barrier?

• yes, through a process called tunneling

• no, because classical physics doesnt allow it

• yes, though a process called fussion

• no, because it is impossible

• yes, through a process called tunneling

Some example of qauntum tunneling include:

• alpha decay

• STM( scanning tunnleing microscopy

• quantum dots

The three steps of scanning tunneling microscope include:

1. small positive voltage of the probe causes electrons to tunnel across the narrow gap between the probe tip and the sample

2. the current is monitored as the probe is moved back and forth across the sample

3. an image shows the current as a function of the position of the probe tip, giving a profile of the surface

Using uranium crystals, physicists Thomson and Rutherford discovered three types of _____- the spontaneous emission of particles or high-energy photons from unstable nuclei as they decay from higher-energy to lower-energy states.

• radioactive decay

• electron decay

• energy decay

• multiactive decay

• radioactive decay

A radioactive sample’s half-life is defined as the time interval in which ___ of a sample of radioactive atoms decays.

• half

• ¼

• doubles

• 1/3

half

Nuclei don’t vanish when they decay. The decayed nuclei have become some other kind of nuclei, called the

• decay nuclei

• half nuclei

• daughter nuclei

• middle nuclei

daughter nuclei

The decay rate is a property of the ___

• electron

• repulsive forces

• decay force

• nucleus

nucleus

Sum of nuclear potenital and coulumb potenital

The original nucleus X is called the ____ nucleus and the decay-product nucleus Y is the daughter nucleus.

• mother

• parent

• original

• first

parent

Beta decay is the emission of an electron (____) or a positron (____):

• beta-minus decay, beta-plus decay

• beta-plus decay, beta minus decay

  -

• beta-minus decay, beta-plus decay

A third form of beta decay occurs when a proton changes into a neutron by ”capturing” an electron from the innermost shell of orbiting electrons. This is called electron ___:

• capture

• decay

• release

• inhibition

• capture

Previously unknown fundamental force, the ____, is responsible for beta decay. 2 The beta decay process emits a particle called a neutrino

• weak interaction

• strong interaction

• vague interaction

• medium interaction

• weak interaction

Nuclei move toward the line of stability by undergoing ___ decay.

• beta

• alpha

• gamma

• neutral

• beta

A proton or a neutron in an excited nuclear state can undergo a quantum jump to a lower-energy state by emitting a high-energy photon. This is the ___-decay process.

• decrease

• increase

• gamma

• alpha

• gamma

The sequence of isotopes, starting with the original unstable isotope and ending with the stable isotope, is called a ___ series.

• lowering

• decrease

• decay

• gamma

• decay

Nuclear imaging, unlike x-ray images, uses internal source radiation from decaying isotopes inside the body.Also, nuclear imaging creates an image of the biological activity of tissues in the body.

A ___ camera, for example, is a device that can measure and produce an image from gamma rays within the body. Its operation is shown below.

• display

• alpha/beta

• gamma

• operation

• gamma

Protons and neutrons must also obey the Pauli exclusion principle. Nuclear shells:

• also follows the same simple rules as electron shells

• don’t follow the same simple rules as electron shells.

• don’t follow the same simple rules as electron shells.

____of the nucleus is based on the shell model of atoms that explains the periodic table of elements.

• The best model

• The decay model

• The gamma model

• The shell model

• The shell model

Proton energy levels are displaced upward in a high- Z nucleus

The net result of beta decay is to keep the levels on both sides filled to just about the same energy.