An aluminum cup of mass 250 g contains 800 g of water in thermal equilibrium at 80.0°C. The combination of cup and water is cooled uniformly so that the temperature decreases by 1.50°C per minute. At what rate is energy being removed by heat? Express your answer in watts.

Rate at which energy is being removed by the heat = 89.625 watts

Explanation:

P = (c₁m₁ + c₂m₂) ΔTₓ

Where P = rate at which energy is being removed by the heat, c₁ = specific heat capacity of water, m₁ = mass of water, c₂ = specific heat capacity of aluminium, m₁ = mass of aluminum, ΔTₓ = rate of temperature decrease.

Where c₂ = 900 J/kgK, m₁ = 800 g = 0.8 kg, m₂ = 250 g = 0.25 kg, c₁ = 4200 J/kgK, ΔTₓ = 1.5°C per minute

P = (4200*0.8 + 900 * 0.25) 1.5

P = (3360 + 225) 1.5

P = (3585) 1.5

P = 5377.5 J / min.

P = 5377.5/60 = 89.625 watts.

Rate at which energy is being removed by the heat = 89.625 watts