Nursing Elites

1. In Einstein’s mass-energy equation, what is represented by c?

• A. Distance in centimeters
• B. The speed of light
• C. Degrees Celsius
• D. Centrifugal force

Correct answer: B

Rationale: In Einstein's mass-energy equation, E=mc^2, the symbol 'c' represents the speed of light in a vacuum, which is approximately equal to 3.00 x 10^8 meters per second. This equation demonstrates the equivalence of energy (E) and mass (m) and is a fundamental concept in the theory of relativity. Choice A is incorrect as 'c' does not represent distance in centimeters. Choice C is incorrect as 'c' does not represent degrees Celsius. Choice D is incorrect as 'c' does not represent centrifugal force.

2. What is the purpose of a switch in a circuit?

• A. To reverse the direction of alternating current
• B. To increase the voltage of the battery or cell
• C. To increase the resistance of wires in the circuit
• D. To allow the circuit to open and close

Correct answer: D

Rationale: The purpose of a switch in a circuit is to allow the circuit to open and close. When the switch is turned on, it provides a complete path for the current to flow through the circuit. When the switch is turned off, it breaks the circuit, stopping the flow of current. This function of opening and closing the circuit using a switch is essential for controlling the flow of electricity in various electrical devices and systems. Choices A, B, and C are incorrect because a switch does not reverse the direction of current, increase voltage, or increase resistance in a circuit; its primary function is to open and close the circuit.

3. Marilyn is driving to a wedding. She drives 4 miles south before realizing that she left the gift at home. She makes a U-turn, returns home to pick up the gift, and sets out again driving south. This time, she drives 1 mile out of her way to pick up a friend. From there, they continue 5 miles more to the wedding. Which of these statements is true about Marilyn’s trip?

• A. The displacement of her trip is 6 miles, and the distance traveled is 6 miles.
• B. The displacement of her trip is 14 miles, and the distance traveled is 14 miles.
• C. The displacement of her trip is 8 miles, and the distance traveled is 14 miles.
• D. The displacement of her trip is 6 miles, and the distance traveled is 14 miles.

Correct answer: C

Rationale: Marilyn’s displacement is calculated based on her final position relative to the starting point. She drives 1 mile to pick up her friend, then 5 miles more to the wedding, totaling 6 miles after returning to her home. So, the correct displacement is 8 miles south from her starting point (4 miles to the gift + 4 miles return + 1 mile to the friend + 5 miles to the wedding). The total distance traveled is 14 miles (adding all the distances). Choice A is incorrect because it miscalculates the displacement. Choice B is incorrect as it overestimates both the displacement and distance traveled. Choice D is incorrect as it underestimates the displacement.

4. Viscosity, μ, is a transport property of a fluid that reflects its:

• A. Inertia
• B. Resistance to flow
• C. Compressibility
• D. Buoyancy generation

Correct answer: B

Rationale: Viscosity refers to a fluid's resistance to flow. A fluid with high viscosity (like honey) flows slowly, while a fluid with low viscosity (like water) flows more easily. It is a measure of internal friction in the fluid. Choice A, 'Inertia,' is incorrect as inertia is the tendency of an object to resist changes in its state of motion. Choice C, 'Compressibility,' is incorrect as it refers to the ability of a fluid to be compressed. Choice D, 'Buoyancy generation,' is incorrect as it relates to the upward force exerted by a fluid that opposes the weight of an immersed object.

5. When a car is driven for a long time, the pressure of air in the tires increases. This is best explained by which of the following gas laws?

• A. Boyle's law
• B. Charles' law
• C. Gay-Lussac's law
• D. Dalton's law

Correct answer: C

Rationale: Gay-Lussac's law, also known as the law of pressure-temperature, states that the pressure of a gas is directly proportional to its absolute temperature when the volume is constant. As a car is driven for a long time, the tires heat up due to friction and increased air pressure inside the tires. This results in an increase in temperature, causing the pressure of the air inside the tires to increase according to Gay-Lussac's law. Choices A, B, and D are incorrect. Boyle's law relates pressure and volume, Charles' law relates volume and temperature, and Dalton's law deals with the partial pressures of gases in a mixture.

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