Nursing Elites

1. Which of the following materials has the lowest density?

• A. Water
• B. Cork
• C. Aluminum
• D. Steel

Correct answer: B

Rationale: Cork has the lowest density among the given options. Cork is a lightweight material derived from the bark of cork oak trees and is known for its low density, making it float on water. Water, aluminum, and steel have higher densities compared to cork. Water is denser than cork because it has a consistent density of 1 g/cm³. Aluminum and steel are metals with much higher densities due to their atomic structures, making them denser than cork.

2. As a vehicle positioned at the peak of a hill rolls downhill, its potential energy transforms into:

• A. Thermal energy
• B. Neither thermal nor kinetic energy
• C. A combination of thermal and kinetic energy
• D. Kinetic energy

Correct answer: D

Rationale: The correct answer is D: Kinetic energy. Potential energy is converted into kinetic energy as the vehicle moves downhill. Kinetic energy is the energy possessed by a moving object. Thermal energy is not produced in this scenario because the energy transformation is mainly from potential to kinetic energy, not involving heat generation. Choices A, B, and C are incorrect because the primary energy transformation in this scenario is from potential to kinetic energy, not involving thermal energy.

3. In hydraulic systems, Pascal's principle states that a pressure change applied to a confined incompressible fluid is:

• A. Amplified but loses energy
• B. Transmitted undiminished throughout the fluid
• C. Limited by the container size
• D. Dependent on the fluid type

Correct answer: B

Rationale: Pascal's principle states that when a pressure change is applied to a confined incompressible fluid, the resulting pressure change is transmitted undiminished throughout the fluid. This means that the pressure change will be the same at every point in the fluid, regardless of the container size or the type of fluid used. Therefore, choice B is the correct answer. Choices A, C, and D are incorrect because Pascal's principle specifically emphasizes the transmission of pressure without amplification, limitation by container size, or dependence on the fluid type.

4. When the heat of a reaction is negative, which statement is true?

• A. The products have less energy and are less stable.
• B. The products have more energy and are more stable.
• C. The products have less energy and are more stable.
• D. The products have more energy and are less stable.

Correct answer: C

Rationale: When the heat of a reaction is negative, it indicates that the reaction releases energy in the form of heat. This means that the products have lower energy levels compared to the reactants. Lower energy levels are associated with greater stability in chemical systems. Therefore, when the heat of a reaction is negative, the products are more stable due to having less energy than the reactants. Choice A, stating that the products have less energy and are less stable, is incorrect as lower energy levels imply greater stability. Choice B, stating that the products have more energy and are more stable, is incorrect as lower energy levels lead to higher stability. Choice D, stating that the products have more energy and are less stable, is incorrect as lower energy levels are associated with higher stability.

5. Which mathematical quantity is scalar?

• A. Distance
• B. Velocity
• C. Acceleration
• D. Displacement

Correct answer: A

Rationale: Distance is a scalar quantity because it has only magnitude and no direction. It is simply the total length of the path travelled by an object. Scalars are quantities that are fully described by their magnitude alone, without any reference to direction. Velocity and acceleration are vector quantities as they have both magnitude and direction. Displacement is also a vector quantity as it is the change in position of an object and includes both magnitude and direction.

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