Particle

Question 1

When formulating a for,Ila involving sqaure roots, what should you do if stuck

Answer 1

Make m say root m2, and see if they cancel out

Or sqaure and square root everything

Question 2

What makes a firce fundamental

Answer 2

If it can explain all interactions

Question 3

List 4 fundamental forces and ranges

Answer 3

Electromagnetic = infinite
Gravational = infinite

String nuclear = fm

Weak nuclear = even less

Question 4

What makes a particle fundamental?

Answer 4

If you can’t split it up anymore, and thus has NO internal structure

In fact all other particles are MADE up from these ones

Question 5

But first what is an antiparticle

Answer 5

Just like energy is conserved, so is mass. All mass created from the Big Bang was created in equal amounts of matter and antimatter

An antiparticle has the same mass as a normal particle but everything else oppsite, charge, strangeness spin etc

Question 6

What is the FIRST DIVISION OF ALL Subatomic particles (matter and antimatter) split into?

Answer 6

HADRONS AND LEPTONS

Question 7

What is the defining feature of a hadron and a lepton

Answer 7

A hadron can experience all 4 fundamental forces, including string nuclear

A lepton can NOT experience string nuclear, only the other 3

This is the distinction

Question 8

What else do all hadrons have that leptons don’t

Answer 8

Hadrons are made up from smaller particles which are fundamental, called QUARKS, whereas leptons are also fundamental

Question 9

So what are all the fundamental particles (so particles that are indivisible and used ti build up everything else)

Answer 9

QUARKS

AND LEPTONS
- electrons and anti
- neutrino and anti

Question 10

What are quarks

Answer 10

There are 6 types of quarks and thus 6 antiquarks , and combinations of these make up all the hadrons we have, so baryons and muons

If 3 quarks make a particle up it will be a baryon (proton neutron), if a quark and antiquark do then a meson

Question 11

For this course what quarks do we need to know

Answer 11

Up
Down
Strange

And all their anti quarks

Question 12

What are hadrons split up into (2 categories ) and how to differentiate rhem

Answer 12

Hadrons = baryon and meson
Baryon made from 3 combo of quark , meson made from a quark and antiquark

Question 13

In terms of hadrons would do we acc need to know for this course

Answer 13

That examples of hadrons are PROTONS AND NEUTRONS (WHICH are baryons)

And their quark combinations, total charge and same for the anti version

Question 14

Proton and neutron quark combo

And their anti version too

Answer 14

PROTON quark = UUD
Neutron = UDD

And anti js just anti etc

Question 15

What are the charges of an UP, DOWN or STRANGE quark?

What about anti?

Answer 15

Up = 2/3 e

Down = -1/3 e

Strange = -1/3 e

Antiparticles are reverse

Question 16

Thus how can you prove using the quark charges the charge in a hadron?

Answer 16

Say proton had charge 1
= UUD, 2/3 + 2/3 -1/3 =1
But antiprotin has charge -1
UUD anti = -2/3-2/3 +-1/3 = -1 AS EXPECTED

Same for neutron etc

Question 17

So how can you remember the quark combination by remembering charged on quark

Answer 17

As long as the charges balance out then you can remember charge in proton must be 1 so UUD etc

Question 18

How does the fact hadrons have quarks show they experience the string nuclear firce?

Answer 18

The quarks themselves are bounded to each other by THE STRONG NUCLEAR FORCE!

so string that you can not separate these from each other, and this just shows you that they can experience the string nuclear force

Question 19

When alpha decay happens, is extra energy produced or what?

So what conservation can we do to find the mass of the daughter nuclei

Answer 19

If not stated then NO

• this for masses can apply conservation of mass using textbook alpha particle to find mass, and then monetum, can do this safe,y because no mass is transfered to energy