A radioactive source is placed in front of a radiation detector.

With nothing between the source and the detector, the registered count rate is $counts/min35\,000 \text{ counts/min}$ .
When a sheet of paper is placed between them, the count rate remains at $counts/min35\,000 \text{ counts/min}$ .
When a 5 mm thick sheet of aluminium replaces the paper, the count rate decreases to $counts/min27\,000 \text{ counts/min}$ .
When a thick lead block replaces the aluminium sheet, the count rate decreases to $counts/min2\,000 \text{ counts/min}$ .

What radiation is being emitted by the source?

$α\alpha$ , $β\beta$ , and $γ\gamma$ radiation

$α\alpha$ and $β\beta$ radiation only

$α\alpha$ and $γ\gamma$ radiation only

$β\beta$ and $γ\gamma$ radiation only

A radioactive source is placed in front of a radiation detector.

With nothing between the source and the detector, the registered count rate is $counts/min35\,000 \text{ counts/min}$ .
When a sheet of paper is placed between them, the count rate remains at $counts/min35\,000 \text{ counts/min}$ .
When a 5 mm thick sheet of aluminium replaces the paper, the count rate decreases to $counts/min27\,000 \text{ counts/min}$ .
When a thick lead block replaces the aluminium sheet, the count rate decreases to $counts/min2\,000 \text{ counts/min}$ .

What radiation is being emitted by the source?

$α\alpha$ , $β\beta$ , and $γ\gamma$ radiation

$α\alpha$ and $β\beta$ radiation only

$α\alpha$ and $γ\gamma$ radiation only

$β\beta$ and $γ\gamma$ radiation only

5.2.2a Alpha, beta and gamma emission

5.2.2a Alpha, beta and gamma emission Questions