HESI A2 Physics Quizlet

Correct Answer: D

Rationale: The correct answer is D. Displacement is the shortest distance between the initial and final points of the walk. Since Jon walks around a rectangular park, his start and end points are the same, hence the displacement is 0 km. The distance traveled is the actual path length covered, which is equal to the perimeter of the rectangle (2+2+1+1=6 km). Therefore, the correct statement is that the displacement of his walk is 0 kilometers, and the distance traveled is 6 kilometers. Summary: A: Incorrect. Displacement cannot be greater than the distance traveled when walking in a closed loop. B: Incorrect. Displacement should be 0 km for a closed loop walk. C: Incorrect. Displacement cannot be greater than the total perimeter of the walk.

Correct Answer: D

Rationale: Step 1: The mechanical power equation is P = E / t, where P is power, E is energy, and t is time. Step 2: Power is the rate at which work is done or energy is transferred. Step 3: The SI unit of power is the watt (W), representing one joule per second. Step 4: Therefore, the correct answer is D: watts. Summary: - A: Ohms is the unit of electrical resistance, not power. - B: Joules is the unit of energy, not power. - C: Volts is the unit of electrical potential difference, not power.

Correct Answer: A

Rationale: As the frequency of a sound wave increases, its wavelength decreases because the speed of sound remains constant in a given medium. This is described by the formula speed = frequency x wavelength. Therefore, when frequency increases, wavelength must decrease to maintain a constant speed. Summary: Choice A is correct because frequency and wavelength are inversely proportional. Choices B, C, and D are incorrect as they do not follow the relationship between frequency and wavelength in a sound wave.

Correct Answer: A

Rationale: The correct answer is A because the second law of thermodynamics states that the total entropy of an isolated system always increases over time in a spontaneous process. This increase in entropy signifies an increase in disorder and randomness within the system and its surroundings. Therefore, choice A is correct as it aligns with the fundamental principle of entropy and the second law of thermodynamics. Choices B, C, and D are incorrect as they contradict this law by suggesting a decrease in total entropy, constancy of entropy, or a decrease in system entropy, respectively.

Correct Answer: A

Rationale: The correct answer is A: Its energy is halved. Kinetic energy is calculated using the formula KE = 0.5 * mass * velocity^2. Since kinetic energy is directly proportional to the square of velocity, if the speed drops from 60 mph to 30 mph, the kinetic energy will be reduced by a factor of 4 (30^2/60^2), which means it is halved. Summary: B: Its energy is doubled - Incorrect. Decreasing the speed from 60 mph to 30 mph reduces the kinetic energy, not double it. C: Its energy is quadrupled - Incorrect. Decreasing the speed results in a decrease in kinetic energy, not quadrupling it. D: Its energy is divided by four - Incorrect. The kinetic energy is reduced by a factor of 4, not divided by four.