1. A machine designed to liquefy nitrogen gas is not working correctly, and the nitrogen remains a gas. This indicates a failure in which fundamental process?
- A. Adding kinetic energy
- B. Increasing molecular attraction
- C. Removing kinetic energy
- D. Decreasing the gas pressure
2. What is the primary role of molecular attraction in the transition of a substance from a gas to a liquid?
- A. It causes molecules to speed up.
- B. It pulls molecules together.
- C. It causes molecules to repel each other.
- D. It breaks molecular bonds.
3. For a gas to successfully condense into a liquid, what change must occur at the molecular level?
- A. The kinetic energy of the molecules must increase significantly.
- B. The forces of molecular attraction must be overcome by the motion of the molecules.
- C. Molecules must lose enough kinetic energy for molecular attraction to pull them together.
- D. The molecules must stop all movement and form a rigid structure.
4. Which statement accurately describes the relationship between the kinetic energy of molecules and the forces of molecular attraction in a typical gas?
- A. The kinetic energy is low, allowing molecular attraction to dominate.
- B. The kinetic energy and molecular attraction are perfectly balanced.
- C. The kinetic energy is high, largely overcoming the forces of molecular attraction.
- D. Molecular attraction is non-existent, and only kinetic energy matters.
5. On a cold day, you see your breath as a small cloud. This cloud is tiny liquid water droplets that have condensed from the water vapor in your warm breath. What energy transfer causes this to happen?
- A. Kinetic energy is transferred from the cold air to your breath, causing condensation.
- B. Your breath transfers kinetic energy to the cold air, causing the water molecules to slow down and condense.
- C. Molecular attraction is created by the cold, pulling water molecules from your breath.
- D. The pressure of the outside air forces the water vapor in your breath into a liquid state.
6. In a system designed to condense gas into a liquid, scientists observe that no liquid is being produced. What is the most likely underlying cause related to energy?
- A. The system is not effectively removing energy from the gas.
- B. The initial amount of gas in the system was insufficient.
- C. The system is generating too much liquid in a hidden compartment.
- D. The system has an excess of energy being added to it from an external source.
7. Based on the model of a functioning system where gas is turned into liquid, which of the following indicates the system is working correctly?
- A. Energy readings are fluctuating wildly.
- B. The system's temperature is steadily rising.
- C. Energy is being efficiently removed.
- D. The amount of gas in the system is increasing.
8. When a scientist compares the energy readings of a broken system to its normal specifications, what is the primary goal?
- A. To prove the machine is broken.
- B. To determine if the machine can be replaced.
- C. To calculate the machine's age.
- D. To identify where the process is failing.
9. In the context of diagnosing a machine, what is the primary purpose of establishing a "baseline"?
- A. To calculate the total cost of the machine's failure.
- B. To provide a standard of normal operation for comparison with a malfunctioning system.
- C. To document the final state of the machine after it has been repaired.
- D. To list all the potential parts that could possibly fail in the future.
10. A technician is called to fix a large air conditioning unit that is not cooling. According to the principles of system diagnosis, what is the most logical first step?
- A. Immediately begin replacing the most expensive components to save time.
- B. Ask the owner how they think the problem started.
- C. Compare the unit's current energy consumption and output to the manufacturer's specifications for normal operation.
- D. Disassemble the entire unit to check every single part.