Name a source of background radiation other than cosmic rays.
State one effect of background radiation.
State how many protons and how many neutrons are in an alpha-particle.
Explain how the Earth’s atmosphere cuts down the number of alpha-particles that reach the surface.
Fig. 11.1 shows a region containing a uniform magnetic field directed into the page. On Fig. 11.1, draw a diagram to show how an alpha-particle is deflected by this magnetic field.
Carbon-14 is produced in the atmosphere by primary cosmic rays. The half-life for carbon-14 is 5700 years. Define the term half-life.
A piece of wood is found to contain 25 000 atoms of carbon-14. An otherwise identical piece taken from a living tree contains 200 000 atoms of carbon-14. Determine the age of the specimen that contains 25 000 atoms of carbon-14.
State why it is not possible to use the amount of carbon-14 to date a specimen that is 570 000 years old.
Carbon-14 is an isotope of carbon, and carbon-12 is another isotope. Describe how a carbon-14 nucleus differs from a carbon-12 nucleus.
Describe one structural similarity between the nuclei of these isotopes.