Nursing Elites

1. According to the law of conservation of energy, energy:

• A. Can be created or destroyed
• B. Can be created, but not destroyed
• C. Can be destroyed, but not created
• D. Cannot be created or destroyed

Correct answer: D

Rationale: The correct answer is D: 'Cannot be created or destroyed.' The law of conservation of energy states that energy cannot be created or destroyed; it can only be transformed from one form to another. This principle is a fundamental concept in physics and is supported by numerous observations and experiments. Choices A, B, and C are incorrect because they do not align with the law of conservation of energy. Energy is a conserved quantity, meaning its total amount remains constant over time, even though it can change forms.

2. Household alternating current typically has a frequency of 60 Hz. Which statement is true?

• A. The circuit is suitable for lighting 60-watt bulbs.
• B. Circuits in the home may carry a current of 60 amperes.
• C. The expected voltage drop is 60 volts per meter.
• D. Electrons complete a cycle 60 times per second.

Correct answer: D

Rationale: The correct answer is D. Electrons complete a cycle 60 times per second when the frequency of the current is 60 Hz. This frequency indicates that the current changes direction 60 times per second, causing the electrons to complete a full cycle back and forth through the circuit at the same rate. Choice A is incorrect because the power rating of a bulb (in watts) is not directly related to the frequency of the current. Choice B is incorrect as typical household circuits do not carry currents as high as 60 amperes. Choice C is incorrect as the expected voltage drop is not measured in volts per meter for household alternating current circuits.

3. A bicycle and a car are both traveling at a rate of 5 m/s. Which statement is true?

• A. The bicycle has more kinetic energy than the car.
• B. The bicycle has less kinetic energy than the car.
• C. Both vehicles have the same amount of kinetic energy.
• D. Only the car has kinetic energy.

Correct answer: B

Rationale: Kinetic energy is determined by both the mass and the velocity of an object. While both the bicycle and the car are moving at the same velocity (5 m/s), the car has significantly more mass than the bicycle. As a result, the car has more kinetic energy than the bicycle, even though their speeds are identical. Therefore, choice B is correct. Choices A, C, and D are incorrect because they do not consider the influence of mass on kinetic energy. Choice A is incorrect as the car has more kinetic energy due to its greater mass. Choice C is incorrect because the vehicles have different masses. Choice D is incorrect as both the bicycle and the car possess kinetic energy.

4. What is the net force acting on the car?

• A. 450 N
• B. 700 N
• C. 1,500 N
• D. 6,300 N

Correct answer: C

Rationale: To determine the net force acting on an object, we need to consider the sum of the forces acting in the same direction and subtract the forces acting in the opposite direction. In this scenario, there is a force of 4,200 N to the right and a force of 2,700 N to the left. By subtracting the leftward force from the rightward force (4,200 N - 2,700 N), we find that the net force acting on the car is 1,500 N to the right. Therefore, choice C, 1,500 N, is the correct answer. Choice A, 450 N, is too small as it does not account for the total forces involved. Choice B, 700 N, is also incorrect as it is not the result of the correct mathematical operation on the given forces. Choice D, 6,300 N, is too large and does not align with the calculation based on the forces provided.

5. An airplane travels 500 miles northeast and then, on the return trip, travels 500 miles southwest. Which of the following is true?

• A. The displacement of the plane is 1,000 miles, and the distance traveled is 0 miles.
• B. The displacement of the plane is 1,000 miles, and the distance traveled is 1,000 miles.
• C. The displacement of the plane is 0 miles, and the distance traveled is 0 miles.
• D. The displacement of the plane is 0 miles, and the distance traveled is 1,000 miles.

Correct answer: D

Rationale: The displacement of an object is the change in position from the starting point to the ending point, regardless of the path taken. In this case, the airplane returns to its original position after traveling 500 miles northeast and then 500 miles southwest. Therefore, the displacement is 0 miles. However, the distance traveled is the total path covered, which is 500 miles northeast plus 500 miles southwest, for a total of 1,000 miles. Choice A is incorrect because the displacement is not the sum of the distances traveled. Choice B is incorrect as it incorrectly states that both the displacement and the distance traveled are 1,000 miles. Choice C is incorrect as it states that both the displacement and the distance traveled are 0 miles, which is not the case.

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