Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

As Physics > Section 1 (Particles and radiation) > Flashcards

Section 1 (Particles and radiation) Flashcards

1
Q

What is the formula and units for specific charge?

A

Specific charge (C/kg)= charge (C) / mass (kg)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is an isotope?

A

Isotopes have the same proton number but different nucleon numbers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is isotopic data?

A

The relative amounts of the different isotopes of an element present in a substance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Explain the forces found in nuclei.

A

Electromagnetic forces cause the positively charged protons to repeal each other. The gravitational force causes all the nucleons to attract each other due to mass. The electromagnetic force is greater than the gravitational force so the strong nuclear force is needed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is alpha decay?

A

The breaking down of atoms with more than 82 protons.

4
O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What happens in beta decay?

A

A neutrino is also emitted because of the conservation of energy.

0 o__
B + V
-1 o e

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How does the strong nuclear and electromagnetic forces vary with nucleon separation?

A

Strong nuclear force is strongest between 0.5fm and 3fm because the electromagnetic force acts here and is weak after 3fm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the order of waves in decreasing wavelength and increasing frequency?

A 
Radio.
Micro.
Infrared.
Visible. 400-750 kHz
UV.
X-Rays. = 10^-10m
Gamma.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the equations for the energy of a photon (with units)?

A

E (J) =
hf (J*Hz) = hc (m/s)
,\ (m)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is pair production?

A

Pair production is when energy is converted into mass, making equal amounts of matter and antimatter. When they both meet the result is annihilation.
For every particle there is a corresponding antiparticle (eg. Electron and positron)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are hadrons?

A

There are 2 types of hadrons- baryons (3) and mesons (2).

Hadrons can feel the sting nuclear force.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are leptons?

A

Leptons can feel the weak force. Lepton numbers must be conserved.

-1 | electron | muon | tau
e ,u t
O | “ neutrino | “…
Ve

Muons decay into electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are baryons?

A

They are made up of 3 quarks.
All baryons except a free proton can be unstable. Al baryons except for protons eventually decay into protons. The Barton number is a quantum number that must be conserved.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are mesons?

A

They are made up of 2 quarks. They interact with baryons via the strong force. Kaons will only decay into pions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe Neuton decay.

A

Neutrons are baryons.
_
n–> p + e- + Ve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What interaction is beta decay cause by?

A

Weak interaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are strange particles?

A

They are produced through the strong interaction.
Strangeness is a quantum number that is conserved in strong interactions.
Strange particles decay through the weak interaction. However, strangeness is not conserved in the weak interaction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the different quarks, their charges and symbols?

A

+2/3 | up | charmed | top
u c t
-1/3 | down |strange |bottom
d s b

19
Q 
Where do the kaons and pions go on the hexagon?
      Strangeness     Charge 
         •       |        •
                  |
--•-------•-------•-'up'ness
                  |
         •       |         •
A 
Strangeness     Charge
     _
1+s          •Ko   |        • K+
                         |
u+d --•-------•no-----•-'up'ness
             n-        |            n+
1+s          •       |         • _
                  K-                K-
20
Q

Where do the deltas, sigmas, Xis and omega go on this table?

Strangeness  Charge
       |
•---•---•---•-->'up'ness
       |
   •---•---•
       |
       •---•
       |
          •
A 
Strangeness  Charge
       |
•---•---•---•-->'up'ness
🔼- no  p+   🔼++  (ddd->uuu)
       |
   •---•---•
   £-   £o   £+
       |
       •---•
       ➡️- ➡️o
       |
          •
          ♎️-                  (sss)
21
Q

What is quark confinement?

A

The energy used trying to remove a u quark only creates a u and anti-u pair in pair production.

22
Q

What happens in B- decay? What force is used?

A

Neutrons ychange into protons.

u--> u
d--> d
d--> u
       '-> e-
w-  |     _
       '-> Ve
23
Q

What happens in B+ decay? What force is used?

A

Protons change into neutrons.

d--> d
u--> u
u--> d
       '-> e+
w+  |     
       '-> Ve
24
Q 
What are the exchange particles, affected particles and decay of the following interactions:
Strong
Electromagnetic
Weak
Gravitational
A

Strong- Pions | Hadrons | Alpha decay
Electromagnetic- Virtual photon | Charged particles | -
Weak- W+/- bosons | all types | B + S decay
Gravitational- Graviton | particles with mass | -

25
Q

What does the diagram for repelling protons look like?

A 
P                              P
  \  virtual photon  /
   ^~~~~~~~~~~~~^
  /                            \
P                                P
26
Q

What does the diagram for B- decay look like?

A 
P                    e-
  \               /  _
    ^     ~ ~  -- Ve
      \~. w-
    /
n
27
Q

What does the diagram for B+ decay look like?

A 
n                    e+
  \               /  
    ^     ~ ~  -- Ve
      \~. w+
    /
P
28
Q

What does the diagram for electron capture look like?

What is the equation?

A 
n                              Ve
  \             W+         /
   ^~~~~~~~~~~~~^
  /                            \
P                                e-

P+e- –> n+Ve

29
Q

What does the diagram for electron- proton collisions look like?

A 
n                              Ve
  \             W-         /
   ^~~~~~~~~~~~~^
  /                            \
P                                e-
30
Q

What does the diagram for electromagnetic repulsion look like?

A 
e+/-                        e+/-
  \  virtual photon  /
   ^~~~~~~~~~~~~^
  /                            \
e+/-                        e+/-
31
Q

What is the relative charge and mass of a proton, neutron and electron?

A

Proton- positive, +1 charge, relative mass 1
Neutron- neutral, 0 charge, relative mass 1
Electron- negative, -1 charge, relative mass 0.0005

32
Q

What is the photoelectric effect?

What is the equation?

A

It’s when you shine radiation onto the surface of a metal. If an electron absorbs enough energy, the bonds holding it to the metal can break and the electron can be released (photoelectrons).
hf= ,0’ + Ek (max)

33
Q

What is the threshold frequency? What is the equation?

A

The frequency the radiation must be for a given metal to begin emitting photoelectrons.
f• = ,0’/ h

34
Q

The number of photoelectrons per second is proportional to…

A

… The intensity of the radiation.

35
Q

What is the equation for Planck’s wave-packets?

A

E=hf=hc/ ,\

36
Q

What is the name for the energy needed to break bonds in the photoelectric effect?

A

The work function

37
Q

Who is de Broglie?

A

He came up with the wave particle duality theory.
,\ (m)= h(J) / mv (kg. m/s)

mv- momentum

38
Q

What is stopping potential?

A

The potential difference needed to stop the fastest moving electrons travelling with kinetic energy.

eVs=Ek
e- charge on electron (C)
Vs- stopping potential (V)
Ek- max kinetic energy (J)

39
Q

Define electron volt (eV).

A

Kinetic energy carried by an electron after it has been accelerated from rest through a potential difference of 1 volt.
1eV=1.6*10^-19 J

40
Q

Explain ionisation and excitation.

A

Ionisation- when an electron is removed from an atom.

Excitation- when energy is transferred to them (when colliding with particles or absorbing a photon)

41
Q

How does a fluorescent bulb work?

A

They contain mercury vapour which a high voltage is applied to. This accelerates fast-moving free electrons that ionise Mercury atoms, producing more free electrons. When they collide the Mercury electrons are excited. When they return to their ground state they lose energy by emitting photons (UV). A phosphorus coating absorbs these and excited it’s electrons to higher energy levels. They then go down the energy levels and emit lower energy photons of visible light.

42
Q

Explain why line spectra are evidence of transitions between discrete energy levels in atoms.

A

Because atoms can only emit photons with energies equal to the difference between two energy levels. You can only see the corresponding wavelengths in the line spectra.

43
Q

Particles have a wave-like nature. Name one way in which we can see this.

A

Electrons can diffract

44
Q

How and why does the diffraction of a particle change when the momentum of a particle changes?

A

A smaller momentum makes the particles diffract more because the wavelength is bigger.

As Physics (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions