Half-life, intro to fission

Question 1

what are the 4 types of radiation

Answer 1

-alpha
-beta
-gamma
-neutrons

Question 2

what is fission?

Answer 2

The splitting of a large and unstable nucleus results in releasing large amount of energy

Question 3

process of fission (step 1)

Answer 3

the nucleus of the large, unstable isotope absorbs a nuetron

Question 4

process of fission (step 2)

Answer 4

this causes the nucleus to split two smaller nuclei that are the approximately the same size

Question 5

process of fission (step 3)

Answer 5

In addition, two or three neutrons, gamma, radiation and lots of energy is released

Question 6

process of fission (step 4)

Answer 6

all the products (smaller nuclei and neutrons) have a large store of kinetic energy

Question 7

what particle is necessary for fission to occur

Answer 7

neutron

Question 8

what particle are released in nuclear fission

Answer 8

neutrons

Question 9

how does the parent nucleus differ from the daughter nuclei ?

Answer 9

parent nuclei is larger (larger mass) than the daughter nuclei.

Question 10

units of activity

Answer 10

Bq

Question 11

what does contamination mean?

Answer 11

there is the unwanted presence of radioactive atom(s) on materials

Question 12

what does irradiation mean?

Answer 12

exposing an object to radiation to destroy micro-organisms

Question 13

what is nuclear radiation used for in medicine ?

Answer 13

-exploration of internal organs
-controlled destruction of unwanted tissue

Question 14

What factors should be considered with risks of radiation

Answer 14

-type of radiation
-half-life of source

Question 15

what are the advantages industrial use of radioactive material

Answer 15

-massive dilution of waste
- reduces concentration (within a given volume) to insignificant levels
-distant from habitation

Question 16

what are the disadvantages of industrial use of radioactive material

Answer 16

-pollution (of the sea/beach)
-mutation or harm to animals or plants
-long period of time necessary

Question 17

count rate per second =

Answer 17

total counts/total time

Question 18

count rate for the sample=

Answer 18

(total counts/total time) -background count rate

Question 19

what does a long half-life have?

Answer 19

radioactive for a longer time, so there is continual exposure

Question 20

what does a short half-life have?

Answer 20

Extremely radioactive initially ,so high exposure, but it will quickly decreases it’s activity to a safe level