How much heat is needed to warm 0.5 kg of a substance with a specific heat of 4186 J/(kg K) by 20 K?
Answer and explanation
Correct answer: D. 4186 J
- Step 1: q = mc(delta T). Step 2. q = 0.5 x 4186 x 20 = 4186 J. Answer: 4186 J. Why not the others: 2093 J: this omits the temperature change. 8372 J: this omits the mass. 0.0024 J: this inverts the formula.
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