Nursing Elites

1. When a dielectric material is inserted between the plates of a charged capacitor, what will happen to the capacitance?

• A. Increase
• B. Decrease
• C. Remain the same
• D. Become unpredictable

Correct answer: A

Rationale: When a dielectric material is inserted between the plates of a charged capacitor, the capacitance will increase. This is because the presence of a dielectric material reduces the electric field between the plates, allowing more charge to be stored for a given voltage, thus increasing the capacitance. Choice B is incorrect because adding a dielectric material increases capacitance. Choice C is incorrect because capacitance changes when a dielectric is added. Choice D is incorrect because the effect of a dielectric on capacitance is predictable.

2. Power (P) represents the rate of work done. Which formula accurately depicts power?

• A. P = W / F
• B. P = d / t
• C. P = W x t
• D. P = F / t

Correct answer: D

Rationale: Power (P) is defined as the rate of work done over time. The correct formula for power is P = W/t, where W is the work done, and t is the time taken. Therefore, option D, P = F / t, correctly represents power as work divided by time. Option A, P = W / F, is incorrect as it represents work divided by force, not power. Option B, P = d / t, is incorrect as it represents distance divided by time, not power. Option C, P = W x t, is incorrect as it represents work multiplied by time, not power. It's important to understand the distinction between work, power, force, time, and other related concepts to solve physics problems accurately.

3. Certain non-Newtonian fluids exhibit shear thickening behavior. In this case, the fluid's viscosity:

• A. Remains constant with increasing shear rate
• B. Decreases with increasing shear rate (shear thinning)
• C. Increases with increasing shear rate
• D. Depends solely on the applied pressure

Correct answer: C

Rationale: When a non-Newtonian fluid exhibits shear thickening behavior, its viscosity increases with increasing shear rate. This means that as more force is applied to the fluid, its resistance to flow also increases, resulting in a higher viscosity. This phenomenon is opposite to shear thinning, where viscosity decreases with increasing shear rate. Therefore, in the case of shear thickening behavior, the correct answer is that the fluid's viscosity increases with increasing shear rate. Choices A, B, and D are incorrect because shear thickening behavior specifically involves an increase in viscosity with increasing shear rate, not remaining constant, decreasing, or depending on applied pressure.

4. For a compressible fluid subjected to rapid pressure changes, sound wave propagation becomes important. The speed of sound (c) depends on the fluid's:

• A. Density (ρ) only
• B. Viscosity (μ) only
• C. Density (ρ) and Bulk modulus
• D. Density (ρ) and Surface tension (γ)

Correct answer: C

Rationale: In a compressible fluid, the speed of sound (c) depends on both the fluid's density (ρ) and Bulk modulus. Density affects the compressibility of the fluid, while Bulk modulus represents the fluid's resistance to compression and plays a crucial role in determining the speed of sound in a compressible medium. Viscosity and surface tension do not directly impact the speed of sound in a compressible fluid subjected to rapid pressure changes. Therefore, the correct answer is C.

5. How do you determine the velocity of a wave?

• A. Multiply the frequency by the wavelength.
• B. Add the frequency and the wavelength.
• C. Subtract the wavelength from the frequency.
• D. Divide the wavelength by the frequency.

Correct answer: A

Rationale: The velocity of a wave can be determined by multiplying the frequency of the wave by the wavelength. This relationship is given by the formula: velocity = frequency × wavelength. By multiplying the frequency by the wavelength, you can calculate the speed at which the wave is traveling. This formula is derived from the basic wave equation v = f × λ, where v represents velocity, f is frequency, and λ is wavelength. Therefore, to find the velocity of a wave, one must multiply its frequency by its wavelength. Choices B, C, and D are incorrect. Adding, subtracting, or dividing the frequency and wavelength does not yield the correct calculation for wave velocity. The correct formula for determining wave velocity is to multiply the frequency by the wavelength.

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