How much heat is needed to raise 2 kg of water (c = 4200 J/kg per degree) by 10 degrees Celsius?
Answer and explanation
Correct answer: C. 84 000 J, from 2 x 4200 x 10
- Step 1: Use Q = m c delta T. Step 2. Q = 2 x 4200 x 10 = 84 000 J. Answer: 84 000 J. Why not the others: Each wrong value drops the mass or shifts a power of ten.
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