physics retrieval 1

what is the radius of an atom

1×10^-10 metres

what is the radius of the nucleus

1×10^-14 metres

which two subatomic particles are found in the nucleus

proton and neutron

what is the relative mass and charge of proton

relative mass= 1 

relative charge= +1

what is the relative mass and charge of a neutron

relative mass= 1

relative charge= 0

what is the relative mass and charge of an electron

relative mass= 0

relative charge= -1

what is the atomic number of an atom

the number of protons in an atom

what is the mass number of an atom

the total number of protons and neutrons in the atom

what makes two atoms the same element

the atoms have the same atomic number

what makes two atoms different isotopes of the same element

same number of protons but different numbers of neutrons

what is an ion

an atom that has gained or lost electrons

what is ionising radiation

radiation with enough energy to remove an electron from an atom

what is nuclear radiation

radiation emitted from the nucleus of an atom

what are the four types of nuclear radiation

alpha, beta, gamma, neutron

what is the activity of a radioactive sample

the average number of radioactive decays detected in the sample each second

what is a count rate

the average number of radioactive decays detected from a sample each second

what are the units used to measure activity and count rate

becquerels

what is the equipment used to measure out count rate

Geiger muller tube or geiger counter

what happens to an electron in an atom when it absorbs radiation

it moves up to a higher shell, further away from the nucleus

what happens to an electron in an atom when it emits radiation

it moves to a lower shell, closer to the nucleus