A2 Daily A Level Physics question
An unopened rigid aerosol can contains gas at 27°C. After being left in the sun, its temperature rises to 127°C. Assuming the gas behaves ideally and the can’s volume is unchanged, what is the new pressure relative to the initial pressure?
Answer
The correct answer is B.
Correct: B — About 1.33 times the initial pressure. At fixed amount and volume, pressure scales with absolute temperature: 27°C = 300 K and 127°C = 400 K, so p2/p1 = 400/300 = 4/3 ≈ 1.33. A is wrong because 0.75 comes from inverting the ratio (300/400) instead of using T2/T1. B is correct because pressure is proportional to Kelvin temperature at constant volume. C is wrong because pressure would only double if the absolute temperature doubled, which it does not (300 K to 600 K would be needed). D is wrong because 1.50 results from rough guessing or mixing Celsius with Kelvin; the correct ratio is 4/3, not 3/2.