Nursing Elites

1. The specific heat capacity (c) of a material is the amount of heat transfer (Q) required to raise the temperature (ΔT) of a unit mass (m) of the material by one degree (typically Celsius). The relationship between these quantities is described by the equation:

• A. Q = cΔT
• B. Q = mcΔT
• C. Q = c / mΔT
• D. Q = ΔT / mc

Correct answer: A

Rationale: The correct equation relating heat transfer (Q), mass (m), specific heat capacity (c), and change in temperature (ΔT) is Q = mcΔT. This equation states that the heat transfer is equal to the product of the mass, specific heat capacity, and temperature change. Therefore, the correct answer is B, as it correctly represents this relationship. Choices C and D do not correctly represent the relationship between these quantities and are therefore incorrect.

2. A 110-volt appliance draws 0 amperes. How many watts of power does it require?

• A. 0 watts
• B. 108 watts
• C. 112 watts
• D. 220 watts

Correct answer: A

Rationale: When a 110-volt appliance draws 0 amperes, it means that the power consumption is zero as well. The formula to calculate power is P = V x I, where P is power in watts, V is voltage in volts, and I is current in amperes. Since the current is 0 amperes, the power required by the appliance is also 0 watts. Therefore, the correct answer is 0 watts. Choice B, 108 watts, is incorrect because there is no current drawn. Choice C, 112 watts, and choice D, 220 watts, are incorrect as well since the appliance is not consuming any power when drawing 0 amperes.

3. For steady, incompressible flow through a pipe, the mass flow rate (ṁ) is related to the fluid density (ρ), cross-sectional area (A), and average velocity (v) via the continuity equation:

• A. ṁ cannot be determined without additional information
• B. ṁ = ρvA
• C. Bernoulli's principle is solely applicable here
• D. The equation of state for the specific fluid is required

Correct answer: B

Rationale: The continuity equation for steady, incompressible flow states that the mass flow rate is the product of the fluid's density, velocity, and cross-sectional area. Hence, ṁ = ρvA. Choice A is incorrect because the mass flow rate can be determined using the given formula. Choice C is incorrect as Bernoulli's principle does not directly relate to the mass flow rate calculation. Choice D is incorrect as the equation of state is not needed to calculate the mass flow rate in this scenario.

4. During an isothermal (constant temperature) expansion, what is the work done by the gas on the surroundings?

• A. Positive and equal to the change in internal energy.
• B. Zero.
• C. Negative and equal to the change in internal energy.
• D. Positive and greater than the change in internal energy.

Correct answer: D

Rationale: In an isothermal expansion, the temperature remains constant, meaning there is no change in internal energy. However, the gas still does work on the surroundings as it expands, and this work is positive. Since internal energy does not change, the correct answer is D, 'Positive and greater than the change in internal energy.' Choice A is incorrect because the work done is not equal to the change in internal energy. Choice B is incorrect as work is done during the expansion. Choice C is incorrect since the work done is not negative during an isothermal expansion.

5. Two objects attract each other with a gravitational force of 12 units. If you double the mass of both objects, what is the new force of attraction between them?

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

Correct answer: C

Rationale: The gravitational force between two objects is directly proportional to the product of their masses. When you double the masses of both objects, the force of attraction between them increases by a factor of 2 x 2 = 4. Therefore, the new force of attraction between the two objects will be 12 units x 4 = 24 units. Choices A, B, and D are incorrect because doubling the mass results in a quadruple increase in force, not a linear one.

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