Nursing Elites

1. In physics, the relationship between acceleration and force is expressed in ___________.

• A. Newton’s first law of motion
• B. Newton’s second law of motion
• C. Newton’s third law of motion
• D. none of Newton’s laws of motion

Correct answer: B

Rationale: The relationship between acceleration and force is expressed in Newton’s second law of motion. This law states that the acceleration of an object is directly proportional to the net force acting on the object and inversely proportional to the object's mass. Mathematically, this relationship is represented as F = ma, where F is the force, m is the mass of the object, and a is the acceleration. Choice A, Newton’s first law of motion, also known as the law of inertia, states that an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an external force. Choice C, Newton’s third law of motion, states that for every action, there is an equal and opposite reaction, focusing on the interaction between two objects. Choice D is incorrect because the relationship between acceleration and force is indeed described by one of Newton’s laws of motion, specifically the second law.

2. Which of the following statements is true about a refrigerator?

• A. It operates on a Carnot cycle and removes heat from a cold reservoir at a lower temperature.
• B. It violates the first law of thermodynamics by creating cold.
• C. It increases the total entropy of the universe.
• D. It operates isothermally at both the hot and cold reservoirs.

Correct answer: A

Rationale: A refrigerator operates on a Carnot cycle by transferring heat from a cold reservoir to a hot reservoir. Choice A is correct because a refrigerator removes heat from a cold reservoir at a lower temperature. Choice B is incorrect as a refrigerator does not violate the first law of thermodynamics but rather requires work input to transfer heat. Choice C is incorrect as a refrigerator does not increase the total entropy of the universe. Choice D is incorrect because a refrigerator does not operate isothermally at both the hot and cold reservoirs.

3. When analyzing a power plant, which of the following is NOT considered a part of the system?

• A. The fuel being burned.
• B. The working fluid (e.g., steam or water).
• C. The turbine that generates electricity.
• D. The surrounding air.

Correct answer: D

Rationale: In a power plant system, the components directly involved in the energy conversion process are considered part of the system. The fuel being burned provides the heat source, the working fluid transfers this heat energy, and the turbine converts it into mechanical energy to generate electricity. The surrounding air, while it may interact with the system, is not a component that directly participates in the energy conversion process within the power plant system. Therefore, the correct answer is D - The surrounding air. Choices A, B, and C are essential components of a power plant system as they play direct roles in the energy conversion process, unlike the surrounding air.

4. A 3-volt flashlight uses a bulb with 60-ohm resistance. What current flows through the flashlight?

• A. o.05 amp
• B. o.5 amp
• C. 1.8 amp
• D. 18 amp

Correct answer: A

Rationale: : Using Ohm's Law, I = V / R: I = 3 / 60 = 0.05 amp. So, the correct current is 0.05 amp.

5. The amount of energy lost in a circuit due to electrical resistance is dissipated in the form of:

• A. Light
• B. Sound
• C. Heat
• D. Mechanical work

Correct answer: C

Rationale: When electrical current flows through a circuit with resistance, energy is lost in the form of heat due to the resistance encountered by the electrons. This dissipation of energy as heat is a common phenomenon in electrical circuits and is known as Joule heating. Therefore, the correct answer is 'Heat.' Light, sound, and mechanical work are not typical forms in which energy is lost due to electrical resistance. Light is not a direct result of energy dissipation in electrical circuits, sound is not a form of energy dissipation in this context, and mechanical work pertains to the application of physical force and not the dissipation of energy due to resistance.

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