Quick answer: use Q = mcΔT, where Q is heat energy, m is mass, c is specific heat capacity and ΔT is the temperature change.
Heat is not temperature
Temperature describes how hot or cold something is. Heat is energy transferred because of a temperature difference. A large cup and a small cup can have the same temperature but need different heat for the same rise.
Worked example
How much heat raises 0.5 kg of water by 10°C if c = 4,200 J/(kg°C)? Q = 0.5 × 4,200 × 10 = 21,000 J. The Celsius temperature difference has the same numerical size as the kelvin difference.
Stuck on a question? Ask it here and get a step-by-step answer in seconds — pay only per answer, no subscription. Ask your doubt now →
Finding a missing quantity
If Q, m and ΔT are known, rearrange: c = Q/(mΔT). Keep mass in kilograms when c is given in J/(kg°C). If the question gives grams, divide by 1,000 first.
Sign and state changes
For a temperature fall, ΔT is negative if you are tracking the object’s energy change. During melting or boiling, heat can change the state without changing temperature; then a latent-heat formula is used instead of Q = mcΔT.
Practice
Find Q for 2 kg of a material with c = 500 J/(kg°C) and a 6°C rise. Answer: 6,000 J.
Use DoubtPay AI to check the substitution and units in a heat numerical; always compare the result with your textbook method.
Stuck on a question? Ask it here and get a step-by-step answer in seconds — pay only per answer, no subscription. Ask your doubt now →