What energy is needed to raise the temperature of 2 kg of water by 10 degrees Celsius? (specific heat capacity of water = 4200 J/kg per degree Celsius)
Answer and explanation
Correct answer: C. 84,000 J
- Step 1: Q = m c (change in temperature). Step 2. Q = 2 x 4200 x 10 = 84,000 J. Answer: 84,000 J. Why not the others: 8,400 J: That is out by a factor of ten. 42,000 J: That is the energy for 1 kg. 840 J: That is out by a factor of one hundred.
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