Nursing Elites

1. A 50-kg box of iron fishing weights is balanced at the edge of a table. Peter gives it a push, and it falls 2 meters to the floor. Which of the following statements is true?

• A. Once the box hits the floor, it loses both its kinetic and potential energy.
• B. The box had kinetic energy only when it was balanced at the edge of the table.
• C. The box had both kinetic and potential energy after it fell.
• D. Once the box hits the floor, it loses all its kinetic energy.

Correct answer: C

Rationale: When the box is balanced at the edge of the table, it has potential energy due to its position above the ground. As Peter gives it a push, and it falls 2 meters to the floor, the box then has both kinetic energy (due to its motion) and potential energy (due to gravity). Therefore, the correct statement is that the box had both kinetic and potential energy after it fell. Option A is incorrect because the box retains its energy forms even after hitting the floor. Option B is incorrect as the box has kinetic energy both before and after falling. Option D is incorrect as the box still possesses kinetic energy even after hitting the floor.

2. Which of the following describes a vector quantity?

• A. 5 miles per hour due southwest
• B. 5 miles per hour
• C. 5 miles
• D. None of the above

Correct answer: A

Rationale: A vector quantity is characterized by both magnitude and direction. In the provided options, choice A, '5 miles per hour due southwest,' fits this definition as it includes both the magnitude (5 miles per hour) and the direction (southwest), making it a vector quantity. Choices B and C only provide the magnitude without indicating any direction, hence they do not represent vector quantities.

3. A caterpillar starts moving at a rate of 14 in/hr. After 15 minutes, it is moving at a rate of 20 in/hr. What is the caterpillar’s rate of acceleration?

• A. 6 in/hr²
• B. 12 in/hr²
• C. 24 in/hr²
• D. 280 in/hr²

Correct answer: C

Rationale: Acceleration is the change in velocity over time. The change in velocity for the caterpillar is 20 in/hr - 14 in/hr = 6 in/hr. Since this change occurred over 15 minutes (or 0.25 hours), the acceleration can be calculated as (6 in/hr) / (0.25 hr) = 24 in/hr². Therefore, the caterpillar's rate of acceleration is 24 in/hr², which corresponds to choice C. Choice A, 6 in/hr², is incorrect as it does not account for the time factor and the correct calculation. Choice B, 12 in/hr², is incorrect as it doubles the correct acceleration value. Choice D, 280 in/hr², is significantly higher than the correct value, indicating a calculation error.

4. A box is moved by a 15 N force over a distance of 3 m. What is the amount of work that has been done?

• A. 5 W
• B. 5 N⋅m
• C. 45 W
• D. 45 N⋅m

Correct answer: D

Rationale: Work done is calculated using the formula: Work = Force x Distance. In this case, the force applied is 15 N and the distance covered is 3 m. Thus, work done = 15 N x 3 m = 45 N⋅m. Therefore, the correct answer is 45 N⋅m. Choice A (5 W) is incorrect because work is measured in joules (J) or newton-meters (N⋅m), not in watts (W). Choice B (5 N⋅m) is incorrect as it miscalculates the work by not multiplying the force by the distance. Choice C (45 W) is incorrect because work is not measured in watts (W) but in newton-meters (N⋅m).

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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