A2 Daily A Level Physics question
Two identical insulated beakers each contain 0.50 kg of liquid at 20°C: one water and one cooking oil. Identical immersion heaters supply the same amount of electrical energy to each. Which statement must be true?
Answer
The correct answer is C.
Correct: C — The oil’s temperature increases more because it has a lower specific heat capacity than water. With the same energy supplied to equal masses, the substance with the lower specific heat capacity undergoes the larger temperature rise. A Water’s thermal conductivity is irrelevant here because the beakers are insulated and the energy input is the same. B Equal energy does not imply equal temperature rise; different specific heat capacities lead to different increases. C This is correct because, for equal mass and energy, temperature rise is larger when the specific heat capacity is smaller. D Density is not the determining factor in this setup; temperature change depends on specific heat capacity per kilogram, not on particles per volume.