In the goil foil experiment, what did the fact that some alpha particles were scattered at angles greater than 90 mean?
They are striking something more massive than themselves
1 of 27
In the goil foil experiment, what did the fact that most alpha particles went straight through mean?
Atoms are mostly empty space
2 of 27
In the goil foil experiment, what did the fact that some alpha particles were deflected at significant angles mean?
The center of the atom must be tiny but contain a lot of mass
3 of 27
In the goil foil experiment, what did the fact that the alpha particles were repelled mean?
The nucleus must have a positive charge and hence since atoms are neutral overall the electrons must be on the outside
4 of 27
What is the equation for closest approach?
r = kQq / kinetic energy
5 of 27
When a particle is at its closest approach, what is its electric potential energy equal to?
Inital kinetic energy
6 of 27
What is special about hadrons?
They feel the strong attraction and are made of quarks
7 of 27
Protons are the only stable baryon, what do the others decay to?
A proton
8 of 27
What is special about leptons?
They dont feel the strong attraction only the weak
9 of 27
Electrons dont decay but what do muons and taus decay to?
A electron
10 of 27
What is the mass and charge of a neutrino?
Zero and zero
11 of 27
What is the difference between a particle and its antiparticle?
Opposite charge and baryon/lepton number
12 of 27
When energy is converted to mass what do you need to make equal amounts of?
Matter and antimatter
13 of 27
What are annihilation and pair-production?
Annihilation is where two particles (matter and anti) convert into energy and pair production is the opposite
14 of 27
What is the charge of a up quark?
+2/3
15 of 27
What is the charge of a down quark?
-1/3
16 of 27
What is the baryon number of any quark?
+1/3
17 of 27
What is the combination of quarks for a proton?
uud
18 of 27
What is the combination of quarks for a neutron?
udd
19 of 27
Why is there no such thing as a free quark?
The energy you would use to try to separate the quarks would actually get changing into a quark antiquark pair
20 of 27
Bosons are exchanged to show forces. What are the bosons and what are they used for?
Gluon for strong, photon for electromagnetic, weak for W+,W-, gravition for gravity
21 of 27
How does a linear accelerator work?
Alternating charge applied to electrodes and timed so that particles are always attracted to the next electrode.
22 of 27
How does a cyclotron work?
Uses two semicircular electrodes to accelerate charged particles across a gap. an alternating pd is applied so the particles are attracted from one side to the other. A magnetic field is applied to keep them moving in a spiral.
23 of 27
How does a synchrotron work?
Electromagnetic keep particles moving in a circular motionz
24 of 27
How do electrons move up and down energy levels?
Emitting and absorbing photons
25 of 27
What does this mean about the energy levels?
They can only take certain values
26 of 27
What is the pauli exclusion principle that fermions obey?
No two fermions can exist in the same quantum state at the same time. So no more than two electrons can be in the same energy level
27 of 27
Other cards in this set
Card 2
Front
In the goil foil experiment, what did the fact that most alpha particles went straight through mean?
Back
Atoms are mostly empty space
Card 3
Front
In the goil foil experiment, what did the fact that some alpha particles were deflected at significant angles mean?
Back
Card 4
Front
In the goil foil experiment, what did the fact that the alpha particles were repelled mean?
Comments
No comments have yet been made