Chapter 11 & 12

Question 1

What two types of particles does the nucleus contain?

Answer 1

Protons & Neutrons

Question 2

The number of protons in the nucleus is given by…

Answer 2

the atomic number, Z.

Question 3

The neutron number, N, is the…

Answer 3

number of neutrons contained in a nucleus.

Question 4

The mass number, A, is the…

Answer 4

total number of protons and neutrons in a nucleus.

Question 5

Protons and neutrons are collectively referred to as

Answer 5

nucleons

Question 6

_______ of a given element have the same number of protons in the nucleus but a different number of neutrons.

Answer 6

Isotopes

Question 7

The 4 fundamental forces

Answer 7

1) Gravity -binds planets to the sun
2) Electromagnetic Force - binds atoms and molecules
3) Weak nuclear force - produces beta decay
4) Nuclear Strong Force - binds the nucleus.

Question 8

Isotopes with unstable nuclei are called

Answer 8

radioisotopes

Question 9

Radioactivity, also called radioactive decay, occurs when…

Answer 9

an unstable nucleus emits radiation.

Question 10

_______ is helium-4 nuclei.

Answer 10

alpha radiation

Question 11

_______ is high energy electrons.

Answer 11

beta radiation

Question 12

_______ is EM radiation.

Answer 12

gamma radiation

Question 13

when an unstable nucleus ejects a helium nucleus, two protons and two neutrons.

Answer 13

Alpha decay occurs

Question 14

When an unstable nucleus ejects an electron.

Answer 14

Beta decay occurs

Question 15

When an excited nucleus ejects a photon.

Answer 15

Gamma decay occurs

Question 16

List the types of radiation in order of least difficult to stop to most difficult to stop.

Answer 16

alpha, beta, gamma

Question 17

Which type of radiation is most difficult to stop?

Answer 17

Gamma radiation

Question 18

When does radioactive decay occur?

Answer 18

Spontaneously
At random
But predictably – like how many times you get 11 after thousands of rolls.

Question 19

The time it takes for half the nuclei in a sample of a radioisotope to decay.

Answer 19

Half-life

Question 20

______ uses the decay-rate of carbon-14 to determine how long ago an organism died.

Answer 20

Carbon-14 dating

Question 21

_______ is naturally created when thermal neutrons in the upper atmosphere bombard N-14.

Answer 21

C-14

Question 22

Considered the fatal dose of radiation.

Answer 22

6 Sv or Gy

Question 23

Something harmful at high doses is beneficial at low doses.

Answer 23

hormesis

Question 24

Implant Radiation Therapy. Radioactive “seeds” placed directly into a cancer tumor.

Answer 24

Brachytherapy

Question 25

Almost all modern “external beam” radiation therapy is done with…

Answer 25

linear accelerators

Question 26

Patient is injected with radioactive isotopes which emit positrons – which collide with electrons to produce gamma rays.

Answer 26

PET Scans

Question 27

______has best spacial imaging.

Answer 27

CT scans

Question 28

______has best functional imaging.

Answer 28

PET Scans

Question 29

The process of multiple treatments over several days.

Answer 29

Fractionation

Question 30

The speed of light

Answer 30

c = 3 * 10^8 m/s

Question 31

The laws of physics are the same for all observers moving uniformly.

Answer 31

• The 1st postulate of special relativity

- aka: the principle of relativity

Question 32

The speed of light is a fundamental constant of nature.

Answer 32

The 2nd postulate of special relativity states:

Question 33

Why is the special theory of relativity “special?”

Answer 33

Because it is restricted to uniform motion.

Question 34

you observe the clock of someone moving, relative to you, to run slower than your clock.

Answer 34

Time dilation

Question 35

you observe the length of an object moving, relative to you, to be less than an identical object at rest, relative to you.

Answer 35

Length contraction

Question 36

This is the apparent shortening of moving objects in the direction of their motion

Answer 36

Length contraction

Question 37

The Universe was created and time began when a point source singularity of “infinite” mass “exploded”

Answer 37

The Hot Big Bang Theory

Question 38

represents a lower frequency due to the Doppler Effect, showing the universe is expanding.

Answer 38

redshift

Question 39

Results in a drastic change in the mass of the nucleus.

Answer 39

Alpha decay