Nursing Elites

1. A wave moves through its medium at 20 m/s with a wavelength of 4 m. What is the frequency of the wave?

• A. 5 s−1
• B. 16 s−1
• C. 24 s−1
• D. 80 s−1

Correct answer: C

Rationale: The formula to calculate the frequency of a wave is given by:

2. The Reynolds number (Re) is a dimensionless quantity used to characterize:

• A. Fluid density
• B. Flow regime (laminar vs. turbulent)
• C. Surface tension effects
• D. Buoyancy force magnitude

Correct answer: B

Rationale: The Reynolds number is a dimensionless quantity used to characterize the flow regime, specifically whether it is laminar (smooth) or turbulent (chaotic). It depends on the velocity of the fluid, its characteristic length (such as pipe diameter), and its viscosity. A low Reynolds number indicates laminar flow, while a high Reynolds number suggests turbulence. Choices A, C, and D are incorrect because the Reynolds number is not related to fluid density, surface tension effects, or buoyancy force magnitude.

3. According to the Law of Universal Gravitation, the gravitational force between two objects is directly proportional to what factor?

• A. the gravitational constant
• B. the distance between them
• C. the product of their masses
• D. the square of the distance between them

Correct answer: C

Rationale: According to the Law of Universal Gravitation, the gravitational force between two objects is directly proportional to the product of their masses. The equation is: F = G × (m₁ × m₂) / r², where F is the gravitational force, G is the gravitational constant, m₁ and m₂ are the masses of the two objects, and r is the distance between them. Choice A is incorrect because the gravitational constant is a constant value. Choice B is incorrect because the distance between the objects affects the strength of the gravitational force inversely proportional to the square of the distance, not directly proportional. Choice D is incorrect as it represents the inverse square law, where the gravitational force decreases with the square of the distance between the objects.

4. A wave in a rope travels at 12 m/s and has a wavelength of 2 m. What is the frequency?

• A. 38.4 Hz
• B. 6 Hz
• C. 4.6 Hz
• D. 3.75 Hz

Correct answer: B

Rationale: The frequency of a wave is calculated using the formula: frequency = speed / wavelength. In this case, the speed of the wave is 12 m/s and the wavelength is 2 m. Therefore, the frequency is calculated as 12 m/s / 2 m = 6 Hz. Choice A (38.4 Hz), Choice C (4.6 Hz), and Choice D (3.75 Hz) are incorrect as they do not result from the correct calculation using the given values.

5. In a circuit with three same-size resistors wired in series to a 9-V power supply, producing 1 amp of current, what is the resistance of each resistor?

• A. 9 ohms
• B. 6 ohms
• C. 3 ohms
• D. 1 ohm

Correct answer: C

Rationale: In a series circuit, the total resistance is the sum of the individual resistances. With a total voltage of 9 V and a current of 1 A, we can use Ohm's Law (V = I × R) to find the total resistance: Total resistance = 9 V / 1 A = 9 ohms. Since the resistors are identical and wired in series, the total resistance is evenly divided among the three resistors: Resistance of each resistor = 9 ohms / 3 = 3 ohms. Thus, the resistance of each resistor is 3 ohms. Therefore, the correct answer is 3 ohms. Choice A, 9 ohms, is incorrect because this would be the total resistance of all three resistors combined in series. Choice B, 6 ohms, is incorrect as it does not account for the equal distribution of resistance in a series circuit. Choice D, 1 ohm, is incorrect as it is too low for resistors in series with a total resistance of 9 ohms.

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