HESI A2 Physics Quizlet

Correct Answer: B

Rationale: The correct answer is B: It is a unique point for each pure substance. The triple point is specific to each substance because it is determined by the unique combination of temperature and pressure at which all three phases can coexist. This is a fundamental property of the substance and remains constant regardless of the container size. Explanation of other choices: A: It can vary depending on the container size - This is incorrect as the triple point is a fixed characteristic of a substance and not influenced by the container size. C: The pressure at the triple point can be zero for some substances - This is incorrect as the triple point requires specific pressure and temperature conditions for all three phases to coexist. D: The temperature at the triple point can be above the boiling point of the liquid phase - This is incorrect as the triple point represents the temperature and pressure at which all three phases can coexist, which is below the boiling point.

Correct Answer: C

Rationale: To calculate work, we use the formula Work = Force × Distance. In this scenario, Amanda exerts a force of 100 N to push the lawnmower a total distance of 20 rows × 30 meters/row = 600 meters. Therefore, the work done is 100 N × 600 m = 60,000 N⋅m. This is why choice C, 60,000 N⋅m, is correct. Choices A and B are incorrect as they do not accurately calculate the work done. Choice D is also incorrect as we can determine the work done using the provided information.

Correct Answer: D

Rationale: To calculate power, we use the formula P = W / t, where P is power, W is work done, and t is time taken. The correct formula is D: P = F / t. Power is the rate at which work is done, so it is the work done per unit time. Therefore, the correct formula depicts power as the force applied divided by the time taken to do the work. Incorrect choices: A: P = W / F - This formula is incorrect because power is not work divided by force. B: P = d / t - This formula is incorrect because power is not distance divided by time. C: P = W x t - This formula is incorrect because power is not work multiplied by time. In summary, choice D is correct because power is defined as work done per unit time, which is represented by force divided by time.

Correct Answer: B

Rationale: To find the diameter of a circle, you simply multiply the radius by 2. In this case, the radius is 6 meters, so the diameter would be 6 x 2 = 12 meters. Therefore, the correct answer is B (12 m). Choice A (6 m) is the same as the given radius, not the diameter. Choices C (18 m) and D (36 m) are incorrect as they are multiples of the radius, not the diameter. The key is to remember that the diameter is always double the radius in a circle.

Correct Answer: D

Rationale: Surface tension is the result of cohesive forces between liquid molecules at the surface, creating a net inward force. When a small object floats on the liquid surface, the surface tension exerts a restoring force towards equilibrium, keeping the object stable. This force pulls the object back towards the liquid surface if it is displaced. This is why choice D, "Restoring force towards equilibrium," is the correct answer. Choices A, B, and C are incorrect. Buoyant force (A) acts on objects immersed in a fluid, not on objects floating on the surface. Pressure difference (B) would not cause sinking of a floating object. Drag force (C) is a resistance force that opposes motion, not related to surface tension in this context.