Alpha particles, beta particles, and gamma rays have different physical characteristics.
Complete the table below by ticking the correct type of radiation for each physical property. The first one has been done for you.
| Property | alpha particles | beta particles | gamma rays |
|---|---|---|---|
| has a positive charge | ✓\checkmark✓ | ||
| is stopped by a few millimetres of aluminium | |||
| is unaffected by magnetic fields | |||
| has the highest ionising power | |||
| consists of high-energy electrons |
The symbol for the nucleus of a phosphorus-32 atom is:
1532P ^{32}_{15}\text{P} 1532PState the number of protons and the number of neutrons in a phosphorus-32 nucleus.
Explain why alpha radiation has a much shorter range in air than beta radiation.
An automated packaging system uses a beta-emitting radioactive source and a detector to monitor the level of laundry detergent powder filling a cardboard box on a conveyor belt.
If a box is underfilled, the detector reading is high. When a fully filled box passes between the source and the detector, the reading drops significantly, as shown in the graph below.
Why is the detector reading never completely constant, even when there is no box passing between the source and the detector?
Why does the detector still record a reading even when the beta-emitting source is completely removed?
Suggest why a fully filled box causes the detector reading to decrease compared to an underfilled box.
