A student investigates the emissions from a radioactive isotope using a Geiger-Müller (GM) tube and counter. The background count rate is first measured to be $(cpm)45\text{ counts per minute (cpm)}$ .

With the radioactive source placed 2.0 cm from the window of the GM tube, the recorded count rate is $cpm980\text{ cpm}$ .

When a sheet of paper is placed between the source and the GM tube, the count rate drops to $cpm320\text{ cpm}$ .
When the paper is replaced by a 6 mm thick aluminium plate, the count rate drops to $cpm45\text{ cpm}$ .

Which types of radiation are emitted by the source?

Beta-minus ( $β−\beta^-$ ) and gamma ( $γ\gamma$ ) only

Alpha ( $α\alpha$ ) and beta-minus ( $β−\beta^-$ ) only

Alpha ( $α\alpha$ ) and gamma ( $γ\gamma$ ) only

Alpha ( $α\alpha$ ), beta-minus ( $β−\beta^-$ ), and gamma ( $γ\gamma$ )

With the radioactive source placed 2.0 cm from the window of the GM tube, the recorded count rate is $cpm980\text{ cpm}$ .

When a sheet of paper is placed between the source and the GM tube, the count rate drops to $cpm320\text{ cpm}$ .
When the paper is replaced by a 6 mm thick aluminium plate, the count rate drops to $cpm45\text{ cpm}$ .

Which types of radiation are emitted by the source?

Beta-minus ( $β−\beta^-$ ) and gamma ( $γ\gamma$ ) only

Alpha ( $α\alpha$ ) and beta-minus ( $β−\beta^-$ ) only

Alpha ( $α\alpha$ ) and gamma ( $γ\gamma$ ) only

Alpha ( $α\alpha$ ), beta-minus ( $β−\beta^-$ ), and gamma ( $γ\gamma$ )

Radioactive emissions

Question 5

Markscheme

Radioactive emissions

Question 5

Markscheme

Radioactive emissions

Question 5

Radioactive emissions Questions

Radioactive emissions

Question 5

Radioactive emissions Questions