An imaging leaflet gives typical effective doses: one chest X-ray 0.020 mSv and one CT examination 4.0 mSv. These values are supplied; you do not need to recall dose units.
.1
Calculate the number of chest X-rays giving the same listed total dose as one CT examination.
[2 marks]
.2
Explain why the dose comparison alone cannot decide whether a patient should have the CT examination.
[3 marks]
6 marksFoundation and Higher
Spec and skills
Original practice question
Answer and supported method checks
A parachutist has reached a first terminal velocity before opening a parachute. Consider the motion from just before opening until a new terminal velocity is reached.
Explain the changes in resultant force, acceleration and speed throughout this sequence.
[6 marks]
6 marksFoundation and Higher
Spec and skills
Original practice question
Answer and supported method checks
A worker is near a sealed radioactive source for a short time. Another worker has radioactive dust on a glove. A supervisor recommends tongs, shielding and careful removal of the contaminated glove.
Explain the different hazards and how the precautions reduce them.
[6 marks]
6 marksHigher
Spec and skills
Original practice question
Answer and supported method checks
A town receives electricity from distant power stations through the National Grid. A pupil proposes removing all transformers because transformers do not create energy.
Evaluate the proposal by explaining the roles of the transformers and the cables.
[6 marks]
5 marksFoundation and Higher
Spec and skills
Original practice question
Answer and supported method checks
In a specific heat capacity investigation, a 0.60 kg block receives 7200 J from a heater. Its temperature rises from 18 °C to 38 °C. A second run with the same block and input energy gives a rise of only 16 °C.
.1
Calculate the specific heat capacity using the first run.
[3 marks]
.2
The student claims that the second run proves the metal has changed. Evaluate the claim and describe one check on the temperature measurement.
