Thermal Properties of Matter is a Class 11 Physics chapter that carries about 2.3% of the Physics questions in NEET. Practise it with 40 questions covering 2 topics, each with an explanation.
Sample questions on Thermal Properties of Matter with answers
8 questions from the practice bank, spread across the chapter's topics. The full set is in the app.
Question 1: Specific Heat, Calorimetry and Heat Transfer
The heat needed to convert 5 g of ice at 0 °C into water at 20 °C is (L = 80 cal/g, c = 1 cal/g °C):
- A 400 cal
- B 500 cal
- C 100 cal
- D 900 cal
Answer: B. 500 cal
Why: Q = 5 × 80 + 5 × 1 × 20 = 400 + 100.
Question 2: Thermal Expansion
A temperature of 300 K is equal to:
- A −27 °C
- B 27 °C
- C 300 °C
- D 573 °C
Answer: B. 27 °C
Why: T(°C) = T(K) − 273.
Question 3: Specific Heat, Calorimetry and Heat Transfer
The boiling point of water increases when the pressure is increased. This is the principle behind the:
- A refrigerator
- B pressure cooker
- C thermos flask
- D hydraulic lift
Answer: B. pressure cooker
Why: The higher boiling point cooks food faster.
Question 4: Thermal Expansion
Water shows an anomalous expansion behavior, having maximum density at:
- A 0°C
- B 4°C
- C 100°C
- D -4°C
Answer: B. 4°C
Why: Unlike most substances, water has its maximum density at 4°C; it expands both when cooled below and heated above this temperature (near freezing), an anomaly important for aquatic life in cold climates.
Question 5: Specific Heat, Calorimetry and Heat Transfer
The specific heat capacity of a substance is defined as the amount of heat required to:
- A melt a unit mass of the substance
- B raise the temperature of a unit mass of the substance by one degree
- C vaporize a unit mass of the substance
- D raise the temperature of the whole sample by one degree
Answer: B. raise the temperature of a unit mass of the substance by one degree
Why: Specific heat capacity is the heat needed to raise the temperature of a unit mass of a substance by 1°C (or 1 K).
Question 6: Thermal Expansion
A metal rod 1 m long at 0 °C is heated to 100 °C. If α = 2 × 10⁻⁵ °C⁻¹, its increase in length is:
- A 20 mm
- B 0.2 mm
- C 2 mm
- D 0.02 mm
Answer: C. 2 mm
Why: Δl = lαΔT = 1 × 2 × 10⁻⁵ × 100 = 2 × 10⁻³ m = 2 mm.
Question 7: Specific Heat, Calorimetry and Heat Transfer
Which mode of heat transfer does not require a material medium?
- A Conduction
- B Convection
- C Radiation
- D Both conduction and convection
Answer: C. Radiation
Why: Radiation transfers heat via electromagnetic waves and can occur through a vacuum, unlike conduction and convection, which both require a medium.
Question 8: Thermal Expansion
The temperature at which the Celsius and the Fahrenheit scales give the same reading is:
- A 100
- B −40
- C 0
- D 32
Answer: B. −40
Why: C = F gives (9/5)C + 32 = C, so C = −40.