A small, glowing-hot iron spark of mass 0.05 g at 1200 ∘C1200\,^{\circ}\text{C}1200∘C is flying near a large, cool lake containing 5.0 × 107 kg of water at 15 ∘C15\,^{\circ}\text{C}15∘C. Which statement is correct?
If the spark falls into the lake, the decrease in the spark's internal energy will be much greater than the increase in the lake's internal energy.
The internal energy of any object depends only on its temperature.
The total internal energy of the water in the lake is less than the total internal energy of the spark.
As the temperature of the spark falls, its internal energy decreases.
151 exam-style questions on CIE IGCSE Physics 2.1.2a Particle structure and motion in solids, liquids and gases. Each one has a worked solution and a mark scheme showing where the marks go.