Chapter 33

Question 1

Isotope

Answer 1

Different number of neutrons, same number of protons

Question 2

Isotones

Answer 2

Same number of neutrons, different number of protons

Question 3

Isobars

Answer 3

Same mass but different numbers of neutrons and protons

Question 4

Atomic mass unit

Answer 4

1/12 of the mass of a C12 atom

Question 5

Value of one meV is

Answer 5

The energy of one atomic mass unit, 931.5

Question 6

Nucleon

Answer 6

Particle of the atomic nucleus, neutron or proton

Question 7

Formula for radius of a nucleus

Answer 7

r=1.2fm * number of nucleons

Question 8

All nuclei have the same density, T/F

Answer 8

True

Question 9

Forces in a nuclei

Answer 9

Coulomb force (repulsion b/w protons)
Strong force/Nuclear force (attraction between protons and neutrons)
Weak force (acts between nuclei but doesn’t play role in binding)
Gravitational

Question 10

Weird thing about strong force

Answer 10

Repulsive if nucleons get close enough, attractive before that point over another short range. Prevents nucleus from collapsing

Question 11

Binding energy

Answer 11

Energy needed to separate nucleus into components

Question 12

Calculate Binding Energy

Answer 12

BE= mass componentsc^2-mass nucleic^2

Can also do it per nucleon

Question 13

Why is a binding energy curve the way it is

Answer 13

At small # of nucleons, not a lot of forces happening, but it increases the more nucleons you add. Past a certain point its too big for forces other than coulomb to act on all the molecules, so it starts binding less tightly again

Question 14

Why can’t you just add neutrons forever

Answer 14

above a certain amount of neutrons they just turn into protons because magic?

Question 15

alpha particle made of

Answer 15

Helium nucleus

Question 16

Positron is the

Answer 16

antiparticle of an electron. Same mass different charge

Question 17

Exponential decay law

Answer 17

N=N0 *e ^-lambda t

Question 18

Decay rate equation and units

Answer 18

R(t) = lambda N(t)
or R(t) = R0 *e^ -lambda t
Units are becquerels (Bq)
1 Bq= 1 decay/s

Question 19

Q value of a reaction

Answer 19

gain or loss of kinetic energy (used as bond energy) in the reaction
Q= Mi - Mf *c^2

Question 20

Things conserved in a nuclear reaction

Answer 20

Charge
Momentum
Angular momentum
Nucleons
NOT MASS

Question 21

decay diagrams axises

Answer 21

Energy on y
atomic number on x
compare daughter and parent

Question 22

Beta decay

Answer 22

change charge by one unit
beta minus emits an electron
beta plus emits a positron

Question 23

Gamma decay

Answer 23

lose energy

Question 24

Isomers

Answer 24

differ in energy state

Question 25

Excited energy state called

Answer 25

metastable state

Question 26

When considering energy emmitted in fission, similar to decay except

Answer 26

also must consider energy of bombarding neutron

Question 27

Absorbed dose versus equivalent dose

Answer 27

Amount of radiation you absorb from an exposure versus how much damage is caused to tissue (absorbed dose times radiation weighing factor)

Question 28

Applications of Nuclear Physics

Answer 28

Bomb detectors

Smoke detectors

Question 29

Triboelectric charging

Answer 29

rub to objects together, positive charge builds up on one, negative charge builds up on the other

Question 30

Current is the

Answer 30

rate of flow of charges (amps)

Question 31

Force of gravity equation

Answer 31

GMm/r^2

Question 32

Electric force equation (Coulomb’s law)

Answer 32

F=kq1q2/r^2

Question 33

How can we measure an electric field?

Answer 33

Put a test charge in it, measure the force on the charge, use E=F/q
We define E as force on a positive test charge

Question 34

Linear charge density equation

Answer 34

u = Q/L
Charge on a linear element
Units of C/m

Question 35

Electric field for continuous charge distribution equation

Answer 35

E= k * delta q/r^2

Question 36

Surface charge equation

Answer 36

Q/A= surface charge

Question 37

Potential Energy between charges equation

Answer 37

U = kQq/r

Question 38

Electric potential of point charge

Answer 38

V=kQ/r

Question 39

Way to find work required to move charge

Answer 39

Find difference in electric potentials intially and finally

multiply it by the charge being moved

Question 40

Electric field lines are ______ to equipotential lines.

Answer 40

perpendicular

Question 41

Equation for change in potential energy

Answer 41

delta U =q delta V

Question 42

An electron volt is

Answer 42

energy change when one elementary charge moves through a potential difference of one volt

Question 43

When a static charge is in a conductor…

Answer 43

there is no electric field component directed along the conductor

Question 44

If you have a charge density question, what do you assume if its an insulator? A conductor?

Answer 44

Insulator you have to choose an assumption, usually that charge is evenly distributed but this doesn’t have to be so
With a conductor all the charge goes to the outer surface

Question 45

We can consider electric flux as a measure of

Answer 45

How many electric field lines pass through a given area

Question 46

Electric flux equation

Answer 46

Electric field times area

Question 47

Guass’s Law

Answer 47

Electric flux through any closed surface is given by the enclosed charge within the region bounded by that surface divided by the permittivity of free space
E delta A = q/(epsilon naught)

Question 48

Magnitude of charge from an infinite line equation

Answer 48

E= u/ (2pi r (epsilon naught))

Question 49

Strength of an electric field of an infinite uniform plane of charge depends on distance from it. True/False

Answer 49

False. Constant at any distance

Question 50

Potential inside a charged conducting shell is constant but not necessarily zero. True/False

Answer 50

True

Question 51

When charges of the same sign are moved together it requires ________ ________ and the _____ ______ ______increases

Answer 51

Positive work

Electric Potential energy