NEET Thermodynamics — Set 8

Question 1

Which law of thermodynamics introduces the concept of temperature as a physical quantity that is equal for systems in thermal equilibrium with a third system?

Accepted Answer

The Zeroth Law of Thermodynamics states that if two systems are each in thermal equilibrium with a third system, they are in thermal equilibrium with each other. This leads to the concept of temperature as a measurable property that is the same for systems in thermal equilibrium.

Question 2

How much heat is required to raise the temperature of $ 0.6 \, \text{kg} $ of copper from $ 20^\circ \text{C} $ to $ 50^\circ \text{C} $? (Specific heat of copper = $ 386.4 \, \text{J kg}^{-1} \text{K}^{-1} $)

Accepted Answer

$ \Delta Q = m s \Delta T $. $ m = 0.6 $, $ s = 386.4 $, $ \Delta T = 50 - 20 = 30 $. $ \Delta Q = 0.6 \times 386.4 \times 30 = 6955.2 \, \text{J} \approx 6955 \, \text{J} $.

Question 3

Which of the following statements is incorrect about reversible processes?

Accepted Answer

Reversible processes require quasi-static conditions and no dissipation, not common in nature where irreversibility dominates. Option C is incorrect.

NEET Physics: Thermodynamics — Practice Set 8

Q1. Which law of thermodynamics introduces the concept of temperature as a physical quantity that is equal for systems in thermal equilibrium with a third system?

Q2. How much heat is required to raise the temperature of \( 0.6 \, \text{kg} \) of copper from \( 20^\circ \text{C} \) to \( 50^\circ \text{C} \)? (Specific heat of copper = \( 386.4 \, \text{J kg}^{-1} \text{K}^{-1} \))

Q3. Which of the following statements is incorrect about reversible processes?

Q4. 0.25 kg of a substance at 30°C absorbs 1500 J of heat, reaching 60°C. What is its specific heat capacity?

Q5. What is the change in internal energy for \( 0.3 \, \text{moles} \) of an ideal gas heated from \( 280 \, \text{K} \) to \( 340 \, \text{K} \) at constant volume? (\( C_v = 20.8 \, \text{J mol}^{-1} \text{K}^{-1} \))

Q6. What thermodynamic property ensures that \( \Delta U \) is zero in a cyclic process?

Q7. A system in a cyclic process absorbs \( 780 \, \text{J} \) of heat and rejects \( 300 \, \text{J} \). What is the net work done?

Q8. A system releases 500 J of heat and has 200 J of work done on it. What is the change in internal energy?

Q9. How much heat is required to raise the temperature of \( 0.35 \, \text{kg} \) of copper from \( 15^\circ \text{C} \) to \( 45^\circ \text{C} \)? (Specific heat of copper = \( 386.4 \, \text{J kg}^{-1} \text{K}^{-1} \))

Q10. In an isobaric process, \( 1 \, \text{mole} \) of an ideal gas expands from \( 8 \, \text{L} \) to \( 16 \, \text{L} \) at \( 360 \, \text{K} \). What is the work done by the gas? (\( R = 8.3 \, \text{J mol}^{-1} \text{K}^{-1} \))