M8 Topic 4: Deep inside the Atom

Question 1

What are the four fundamental forces (weakest ➞ strongest)

Answer 1

1. Electromagnetism
2. Weak force
3. Strong force
4. Gravitation

Question 2

What is gravitation and what is its range

Answer 2

• the force that acts between object with mass

- Range infinite

Question 3

What is the force carrier particle for gravitation

Answer 3

Graviton

Question 4

What is the weak force and what is it’s range

Answer 4

• The force that is responsible for radioactive decay

- Range: short

Question 5

What is the force carrier particle for the weak force

Answer 5

Weakons ( W⁺, W⁻, Z⁰)

Question 6

What is electromagnetism and what range does it have

Answer 6

• the force that act between charged particles

- Range: infinite

Question 7

What is the force carrier particle for electromanetism

Answer 7

Photon (γ)

Question 8

What is the strong force and what is its range

Answer 8

• the force that binds quarks together

- short range

Question 9

What is the force carrier particle for the strong force

Answer 9

gluons (𝓰)

Question 10

When do nucleuses become unstable (2)

Answer 10

• when they don’t have the correct ratio between protons and neutrons
• when on a graph of proton number against neutron number is unstable if outside of the belt of stability

Question 11

what is alpha decay

Answer 11

the loss of a helium nucleus

Question 12

what is beta minus decay

Answer 12

neutron ➞ proton + electron + antineutrino

Question 13

What is beta plus decay

Answer 13

proton ➞ neutron + positron + neutrino

Question 14

What is gamma decay

Answer 14

the release of gamma rays to lower the amount energy(lower energy level) within the nucleus

Question 15

what is the radioactive decay law (half life equation)

Answer 15

N = N₀e^-λt (m=m₀e^-λt mass iteration) (A = N₀e^-λactivity interation

Question 16

what does each symbol of the radiactive decay law (half life equation mean and what units are they measured in)

Answer 16

N = number of nuclei at time measured
N₀= initial amount of nuclei
λ = decay constant (s⁻¹)
t = time passed (t)

m= mass at time measured
m₀ = mass intial

A = activity in decay per second (Bq)

Question 17

what is the unit for the rate of decay

Answer 17

becquerel (Bq) = decays per second

Question 18

What is binding energy and what those it indicate

Answer 18

• the energy required to separate an atom into seperate parts
• the more binding energy the more stable the nucleus

Question 19

What element has the highest binding energy

Answer 19

Iron (Fe)

Question 20

What is fission

Answer 20

the breaking apart of a nucleus

Question 21

which elements can go through fission

Answer 21

Uranium 236

Question 22

why do elements go through fission

Answer 22

• as strong force only works over a very short distance, the larger the distance the less influence
• Larger the neutron the more influence electrostatic has at repelling the protons

Question 23

What does uranium turn into when it enter nuclear fission

Answer 23

uranium 236 ➞ krypton 92 + Radium 141 + 3 neutrons

Question 24

What are the components of a fission reactor (5)

Answer 24

• fuel rods
• moderator
• control rods
• coolant
• radiation shield

Question 25

what is the role of the fuel rods and what are they made out of

Answer 25

• to release the energy from the breakdown of fissionable material, the daughter nucleus and neutrons
• material: Enriched uranium (uranium with 5% U-235)

Question 26

what is the role of the moderator and what is it made out of

Answer 26

• slows neutrons to increase chance of fission events

- Material: water or heavy water (graphite ions)

Question 27

what is the role of control rods and what are they made out of

Answer 27

• absorb excess neutrons in order to control the rate of thermal energy production
• Material: cadmium

Question 28

what is the role of coolant and what is it made out of

Answer 28

• to absorb thermal heat produced in the reaction to prevent overheating
• material: water

Question 29

What is the role of the radiation shield and what is it made out of

Answer 29

• it absorbs potentially harmful radiation from escaping from the reactor core
• material: lead + thick concrete