Physics (GCSE) Revision (Radioactivity)
Quiz yourself by thinking what should be in
each of the black spaces below before clicking
on it to display the answer.
Help!
|
|
|
||||||
|---|---|---|---|---|---|---|---|---|
| Some substances give out radiation all the time, whatever is done to them. They are said to be . . . | radioactive. | show 🗑
|
||||||
| There are three types of radiation emitted by radioactive sources . . . | alpha, beta and gamma. | show 🗑
|
||||||
| Alpha radiation is easily absorbed by . . . | thin sheets of paper or a few cm of air. | show 🗑
|
||||||
| Alpha particles are actually composed of . . . | helium nuclei. | show 🗑
|
||||||
| Beta particles are actually . . . | show | They are emitted from the nucleus but they are the same as those in orbit round it.
🗑
|
||||||
| Gamma rays are . . . | a form of electromagnetic radiation. | show 🗑
|
||||||
| Beta particles travel at nearly the speed of light but are mostly absorbed by . . . | a few mm of metal. | show 🗑
|
||||||
| Gamma rays are very penetrating and can only be absorbed by . . . | show | They do not interact very strongly with matter so are difficult to stop.
🗑
|
||||||
| There are radioactive substances all around us, particularly in . . . | the ground, air, in building materials and food. It is known as background radiation. | show 🗑
|
||||||
| show | cosmic rays. | They are produced in supernova explosions.
🗑
|
||||||
| When radiation from radioactive materials collides with neutral atoms or molecules, they may become . . . | ionised (charged) | show 🗑
|
||||||
| When radiation ionises molecules in living cells it can cause damage, including . . . | cancer. | show 🗑
|
||||||
| Higher doses of radiation are used to . . . | kill cancer cells and harmful micro-organisms. | show 🗑
|
||||||
| As radiation passes through a material it can be . . . | show | The greater the thickness, the more is absorbed.
🗑
|
||||||
| The absorption of radiation can be used to . . . | show | For example, paper or aluminium 'bacofoil'
🗑
|
||||||
| When sources of radiation are outside the body, which types are most dangerous? | Beta and gamma | show 🗑
|
||||||
| Outside the body, which type of radiation is least dangerous? | show | because it cannot penetrate the outer layers of clothing or skin.
🗑
|
||||||
| Workers who are at risk from radiation wear a film badge. Why? | show | Different layers of absorbers on top of the film can tell us what type of radiation has caused the exposure.
🗑
|
||||||
| When sources of radiation are inside the body, which are most dangerous? | Alpha | show 🗑
|
||||||
| show | Beta and gamma | because they can escape the body and are less likely to be absorbed.
🗑
|
||||||
| The half life of a radioactive substance is . . . | show | This is an average time - decay is a random process.
🗑
|
||||||
| The half life of a substance can also be . . . | show | The rate of decay is proportional to the number of radioactive atoms in a sample.
🗑
|
||||||
| The nucleus which emits radiation is referred to as a parent. What is its decay product called? | show | That's politically correct at least!
🗑
|
||||||
| Radioactive isotopes are used as tracers. What is a tracer? | show | Beta and gamma radiation are usually used for this.
🗑
|
||||||
| What type of radiation would be most suitable for use as a biological tracer in a patient? | show | because it is not easily absorbed by the cells and will cause little damage.
🗑
|
||||||
| Atoms have a small nucleus made up of . . . | protons and neutrons | show 🗑
|
||||||
| Electrons are negatively charged and are usually found . . . | show | They are NOT like planets going around the Sun !
🗑
|
||||||
| show | To fire alpha particles at a sheet of gold foil. | Why gold foil ?
(The foil can be made very thin so that the alpha particles only made single collisions with gold atoms.)
🗑
|
||||||
| show | The nucleus is tiny, very massive and positively charged. | JJThomson thought it was like a plum pudding - how daft !
🗑
|
||||||
| In Rutherford's experiment, what were the main observations? | show | Like a cannonball reflecting from tissue paper !
🗑
|
||||||
| All atoms of the same element have the same number of . . . | Protons | show 🗑
|
||||||
| show | Protons and electrons | Now I care !
🗑
|
||||||
| show | atoms of the same element which have different numbers of neutrons in the nucleus. | You can forget the electrons now.
🗑
|
||||||
| The total number of protons and neutrons in an atom is called its . . . | mass or nucleon number. | show 🗑
|
||||||
| show | changes in the nuclei of atoms. | Electrons are NOT involved in nuclear Physics.
🗑
|
||||||
| show | radioisotopes or radionuclides | They have UNSTABLE nuclei which split up and emit radiation.
🗑
|
||||||
| show | becomes a different nucleus with a different number of protons and neutrons. | The electrons just hang around until something better comes along.
🗑
|
||||||
| show | there is no change to the structure of the nucleus - it just cools down a bit. | Gamma rays have no mass or charge - they just carry energy away from the nucleus.
🗑
|
||||||
| Alpha decay results in the nucleus losing . . . | 2 protons and 2 neutrons | show 🗑
|
||||||
| show | a neutron changes into a proton - it emits an electron which takes away negative charge. | Bit like a sex change !
🗑
|
||||||
| show | the less radiation it emits. | Can be used to date materials and rocks.
🗑
|
||||||
| show | nuclear fission. | A heavy nucleus (uranium) absorbs a slow neutron and splits ( fissions) into two lighter nuclei plus neutrons.
🗑
|
||||||
| show | they are hard to dispose of properly. | They must be stored carefully for hundreds of years.
🗑
|
||||||
| The energy released during nuclear fission is . . . | show | Those involving electrons !
🗑
|
||||||
| Uranium isotopes which have a long half life, decay by a series of short-lived isotopes to produce . . . | stable isotopes of lead. | show 🗑
|
||||||
| The age of a rock can be found by comparing . . . | the relative proportions of uranium and lead in the rock. | show 🗑
|
||||||
| show | its stable decay product argon is unable to escape from the rock. | Apply the idea of half life to the ratio of what remains to what was there initially.
🗑
|
||||||
| show | Two half lives | because only 1/4 of the original potassium remains.
🗑
|
||||||
| Carbon-14 is a radioactive isotope of carbon-12. How is it used? | show | Living things breathe in C14 while alive, but after death the C14 decays to Nitrogen.
🗑
|
||||||
| How much of radioactive material X remains after 3 half lives | show | 1/2 x 1/2 x 1/2 = 1/8
🗑
|
Review the information in the table. When you are ready to quiz yourself you can hide individual columns or the entire table. Then you can click on the empty cells to reveal the answer. Try to recall what will be displayed before clicking the empty cell.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Created by:
J Thomson
Popular Physics sets