1. The branch of physics that deals with the relationship between heat and other forms of energy is called:
Answer:
Explanation:
Thermodynamics deals with the conversion of energy from one form to another, especially the conversion of thermal energy to and from other forms of energy.
2. Which law of thermodynamics introduces the concept of entropy?
Answer:
Explanation:
The second law of thermodynamics introduces the concept of entropy as a measure of the amount of energy in a physical system that cannot be used to do work.
3. For a reversible isothermal expansion of an ideal gas, the work done is given by:
Answer:
Explanation:
For a reversible isothermal process involving an ideal gas, the work done is given by the formula W = nRT ln(V2/V1).
4. In a cyclic process, the change in internal energy is:
Answer:
Explanation:
In a cyclic process, the system returns to its initial state, so the change in internal energy is zero.
5. Which of the following processes is NOT spontaneous?
Answer:
Explanation:
Spontaneous processes occur without any external intervention. Water flowing uphill is non-spontaneous as it defies gravity.
6. The efficiency of a Carnot engine operating between temperatures T1 and T2 is given by:
Answer:
Explanation:
The efficiency of a Carnot engine is given by 1 – (T2/T1).
7. Which of the following statements is TRUE for an isochoric process?
Answer:
Explanation:
An isochoric process is a thermodynamic process in which the volume remains constant.
8. The amount of heat transferred to or from a system at constant pressure is called:
Answer:
Explanation:
Enthalpy is a measure of the total energy of a thermodynamic system. It includes the internal energy, which is the energy required to create a system, and the amount of energy required to make room for it by displacing its environment and establishing its volume and pressure.
9. What is the change in entropy for a reversible adiabatic process?
Answer:
Explanation:
For a reversible adiabatic process, there is no heat exchange, hence the change in entropy is zero.
10. Which of the following is NOT a state function?
Answer:
Explanation:
A state function depends only on the current state of the system, not on the way in which the system acquired that state. Work is not a state function because it is path-dependent.
11. The entropy of a perfectly crystalline substance at absolute zero is:
Answer:
Explanation:
According to the third law of thermodynamics, the entropy of a perfect crystal is exactly zero at absolute zero.
12. Which of the following represents the First Law of Thermodynamics?
Answer:
Explanation:
The First Law of Thermodynamics, also known as the Law of Energy Conservation, states that energy cannot be created or destroyed in an isolated system. The change in internal energy (ΔE) of a system is equal to the heat (q) added to the system minus work (w) done by the system on its surroundings.
13. The heat death of the universe is a theoretical event where the universe will attain a state of:
Answer:
Explanation:
The heat death hypothesis is based on the idea that the universe will eventually reach a state of maximum entropy, or complete disorder, where no thermodynamic free energy will remain, making it impossible to produce work and achieve a change of state.
14. A process in which no heat exchange takes place with the surroundings is called:
Answer:
Explanation:
An adiabatic process is one where there is no heat transfer into or out of the system. The system is perfectly insulated.
15. In which of the following processes is work done only because of a volume change?
Answer:
Explanation:
In isothermal expansion, the temperature remains constant. Here, work is done only due to a change in volume.