An aluminum container of mass 0.15 kg contains 0.25 kg of water. The specific heat capacity of aluminum is 900 J/(kg ∘C)900\text{ J}/(\text{kg }^\circ\text{C})900 J/(kg ∘C) and the specific heat capacity of water is 4200 J/(kg ∘C)4200\text{ J}/(\text{kg }^\circ\text{C})4200 J/(kg ∘C). How much energy, in joules, is needed to raise the temperature of the aluminum container and the water by 15∘C15^\circ\text{C}15∘C?
(0.15×900×15)−(0.25×4200×15)(0.15 \times 900 \times 15) - (0.25 \times 4200 \times 15)(0.15×900×15)−(0.25×4200×15)
(0.15×900×15)+(0.25×4200×15)(0.15 \times 900 \times 15) + (0.25 \times 4200 \times 15)(0.15×900×15)+(0.25×4200×15)
(0.15+0.25)×(900+42002)×15(0.15 + 0.25) \times \left(\frac{900 + 4200}{2}\right) \times 15(0.15+0.25)×(2900+4200)×15
(0.15+0.25)×(900+4200)×15(0.15 + 0.25) \times (900 + 4200) \times 15(0.15+0.25)×(900+4200)×15
528 exam-style questions on CIE IGCSE Physics 2.2 Thermal properties and temperature, covering 2.2.1 Thermal expansion of solids, liquids and gases, 2.2.2a Internal energy and temperature, 2.2.2b Specific heat capacity, 2.2.3a Melting, boiling, condensation and solidification, 2.2.3b Evaporation, and 2.2.3c Cooling by evaporation. Each one has a worked solution and a mark scheme showing where the marks go.