100 g of water is heated from 30^ to 50^ . Ignoring the slight expansion of the water, the change in its internal energy is (specific heat of water is - Physics MCQ FIITJEE AIEEE 2011 (Set Q) 2026 | ExamTest.live

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100 g of water is heated from 3 0^{\circ} C to 5 0^{\circ} C . Ignoring the slight expansion of the water, the change in its internal energy is (specific heat of water is 4184 J/kg/K):

Solution & Step-by-step Explanation

Change in heat Q = m c Δ T . m = 0.1 kg, c = 4184 J/kg/K, Δ T = 50 - 30 = 20 K . Q = 0.1 \times 4184 \times 20 = 8368 J \approx 8.4 kJ Since expansion is ignored, work done W \approx 0 .By First Law: Δ U = Q - W \approx 8.4 kJ .

Try it yourself before checking the explanation above.

100 g of water is heated from 3 0^{\circ} C to 5 0^{\circ} C . Ignoring the slight expansion of the water, the change in its internal energy is (specific heat of water is 4184 J/kg/K):

8.4 kJ

84 kJ

2.1 kJ

4.2 kJ

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