space physcis/ radiation

Question 1

describe the process of nuclear fission

Answer 1

when an unstable nucleus splits into 2+ nuclei, releasing a lot of energy

Question 2

describe the process of nuclear fusion

Answer 2

2 nuclei join to make one large nucleus, releasing energy

Question 3

what is needed for nuclear fusion to occur?

Answer 3

Very high temperatures and pressure.

Question 4

what is needed for nuclear fission to occur?

Answer 4

neutrons (acts as catalyst)

Question 5

What is used to limit the rate of nuclear fission?

Answer 5

control rods (absorbs neutrons)

Question 6

what is alpha radiation?

Answer 6

a slow-moving, positively charged particle.

Question 7

what is beta radiation?

Answer 7

a fast-moving, negatively charged particle

Question 8

what is Gamma radiation?

Answer 8

electromagnetic radiation that travels at the speed of light

Question 9

what does alpha radiation consist of?

Answer 9

2 protons and 2 neutrons (2+ charge)

Question 10

What stops alpha radiation?

Answer 10

air

Question 11

what stops beta radiation?

Answer 11

thin foil

Question 12

what stops gamma radiation?

Answer 12

thick lead or concrete

Question 13

How does alpha radiation change an element’s atomic number and mass number?

Answer 13

+ 4 to top ( mass)
- 2 to bottom ( atomic)

Question 14

How does beta radiation change an element’s atomic number and mass number?

Answer 14

+0 to top (mass)
+1 to bottom (atomic)

Question 15

how can gamma rays be used in medicine?

Answer 15

for killing cancer cells

Question 16

what is a radioisotope?

Answer 16

a radioactive isotope

Question 17

what is an isotope?

Answer 17

2+ forms of an element that contain the same amount of protons but a different number of neutrons.(different atomic mass)

Question 18

define irradiation

Answer 18

the proccess where objects are exposed to radiation

Question 19

define contamination

Answer 19

when radioactive particles get onto other objects

Question 20

why is alpha radiation harmful in the body but not harmful if outside?

Answer 20

as alpha can enter cells and harm them, however alpha cannot penetrate air or skin if outside of the body

Question 21

what is radiotherapy?

Answer 21

using radiation to kill unwanted cells

uses gamma rays if external
uses beta rays if internal

Question 22

what are medical tracers?

Answer 22

inserting isotopes into the body to track the movement of radiation
this can ensure organs are working properly

uses gamma radiation as it is less ionising

Question 23

compare nuclear fission and fusion

Answer 23

fission- more radioactive waste
fusion - alot more expensive
fission- produces way more energy