physics - energy

Question 1

how can an unstable nucleus become more stable over time

Answer 1

an unstable nucleus can become more stable over time by randomly (spontaneously) emitting ionising radiation. This process is called radioactive decay

Question 2

what are radioactive substances

Answer 2

substances that decay radioactively

Question 3

what are beta particles

Answer 3

electrons

Question 4

three ways of detecting radioactivity

Answer 4

cloud chamber
photographic film
Geiger counter

Question 5

properties of alpha radiation

Answer 5

each alpha particle contains 2 protons and 2 neutrons so they have a a relative mass of 4
alpha particles are big and heavy so they are highly ionising
does a lot of damage but can be stopped by a thin sheet of paper

Question 6

properties of gamma radiation

Answer 6

weakly ionising
stopped by centimetres of led or metres of concrete
does not cause as much damage as alpha or beta particles