Specific heat capacity is the amount of heat required to raise the temperature of unit mass of a substance by 1°C (or 1 K).
Specific heat capacity of a substance is the heat required to raise the temperature of 1 kg of the substance by 1°C.
Q = m c ΔT
where,
Q = heat supplied (J)
m = mass (kg)
c = specific heat capacity (J kg−1 K−1)
ΔT = change in temperature (°C or K)
The SI unit of specific heat capacity is J kg−1 K−1.
Q1. Specific heat capacity is the heat required to: A) Raise temperature of any mass by any amount B) Raise temperature of unit mass by 1°C C) Melt a substance D) Change state Answer: B Q2. Formula for heat supplied is: A) Q = m + c + ΔT B) Q = m c ΔT C) Q = m / c ΔT D) Q = m ΔT / c Answer: B Q3. SI unit of specific heat capacity is: A) J kg⁻¹ B) J K⁻¹ C) J kg⁻¹ K⁻¹ D) kg J⁻¹ K⁻¹ Answer: C Q4. A substance with high specific heat capacity: A) Heats up quickly B) Cools quickly C) Heats up slowly D) Cannot be heated Answer: C Q5. Which substance has high specific heat capacity? A) Iron B) Copper C) Water D) Aluminium Answer: C Q6. Heat required to raise temperature depends on: A) Mass only B) Specific heat only C) Temperature change only D) Mass, specific heat and temperature change Answer: D Q7. Unit mass in SI system is: A) gram B) kilogram C) tonne D) milligram Answer: B Q8. Sea breeze is due to: A) Expansion of air B) Low pressure C) Difference in specific heat of land and water D) Rotation of Earth Answer: C
Heat required to raise temperature of 1 kg of a substance by 1°C.
Q = m c ΔT
J kg−1 K−1
Numericals are frequently asked using Q = m c ΔT. Pay attention to units.
