Nursing Elites

1. Which of the following describes a vector quantity?

• A. 5 miles per hour due southwest
• B. 5 miles per hour
• C. 5 miles
• D. None of the above

Correct answer: A

Rationale: A vector quantity is characterized by both magnitude and direction. In the provided options, choice A, '5 miles per hour due southwest,' fits this definition as it includes both the magnitude (5 miles per hour) and the direction (southwest), making it a vector quantity. Choices B and C only provide the magnitude without indicating any direction, hence they do not represent vector quantities.

2. Two objects attract each other with a gravitational force of 12 units. If you double the distance between the objects, what is the new force of attraction between the two?

• A. 3 units
• B. 6 units
• C. 24 units
• D. 48 units

Correct answer: A

Rationale: The gravitational force between two objects is inversely proportional to the square of the distance between them. If the distance is doubled, the force will be reduced to 1/4 of the original force. Therefore, the new force of attraction between the two objects will be 12 units / 4 = 3 units. Choice A is correct because doubling the distance reduces the force to 1/4 of the original value. Choices B, C, and D are incorrect as they do not consider the inverse square relationship between distance and gravitational force.

3. When a fluid encounters a bluff body (e.g., a car), the flow can separate behind the object, creating a region of low pressure. This phenomenon is known as:

• A. Cavitation
• B. Boundary layer separation
• C. Bernoulli effect per se
• D. Drag crisis

Correct answer: B

Rationale: The correct answer is B: Boundary layer separation. Boundary layer separation occurs when the flow of fluid detaches from the surface of a bluff body, leading to a low-pressure region behind the object. This separation creates a wake region with reduced pressure. Choice A, Cavitation, refers to the formation of vapor bubbles in a fluid and is not relevant in this context. Choice C, Bernoulli effect per se, does not specifically describe the phenomenon of flow separation behind a bluff body. Choice D, Drag crisis, is not the term used to describe the creation of a low-pressure region due to flow separation.

4. 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.

5. In an adiabatic process, there is:

• A. No heat transfer (Q = 0) between the system and the surroundings.
• B. Isothermal compression or expansion (constant temperature).
• C. Constant pressure throughout the process (isobaric process).
• D. No change in the system's internal energy (energy is conserved according to the first law).

Correct answer: A

Rationale: In an adiabatic process, choice A is correct because adiabatic processes involve no heat transfer between the system and its surroundings (Q = 0). This lack of heat transfer is a defining characteristic of adiabatic processes. Choices B, C, and D do not accurately describe an adiabatic process. Choice B refers to an isothermal process where temperature remains constant, not adiabatic. Choice C describes an isobaric process with constant pressure, not specific to adiabatic processes. Choice D mentions the conservation of energy but does not directly relate to the absence of heat transfer in adiabatic processes.

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