HESI A2 Physics

Correct Answer: A

Rationale: In an adiabatic process, there is no heat transfer between the system and the surroundings (choice A is correct). This is because adiabatic processes occur without any heat exchange, so the heat transfer (Q) is zero. The other choices are incorrect because in an adiabatic process, there is no requirement for constant temperature (choice B), constant pressure (choice C), or no change in internal energy (choice D). Adiabatic processes focus on the absence of heat transfer, not necessarily on the maintenance of specific temperature, pressure, or energy conditions.

Correct Answer: D

Rationale: The correct answer is D because salt increases the density of water, making it more buoyant. Higher water density provides greater buoyant force on the boat, allowing it to float more easily. Choices A, B, and C are incorrect as salt does not directly affect the mass of the boat, the volume of water, or the density of the boat itself.

Correct Answer: C

Rationale: The correct answer is C because longitudinal waves have vibrations that move in the same direction as the wave propagation. In a longitudinal wave, the particles oscillate parallel to the direction of the wave's movement, creating compressions and rarefactions. Option A is incorrect as vibrations in longitudinal waves are not perpendicular. Option B is incorrect because vibrations do not move in the opposite direction of the wave. Option D is incorrect as waves and troughs are not relevant to the direction of vibrations in longitudinal waves.

Correct Answer: B

Rationale: The correct answer is B: The bicycle has less kinetic energy than the car. Kinetic energy is calculated as KE = 0.5 * mass * velocity^2. Since both vehicles are traveling at the same speed, the one with greater mass (the car) will have more kinetic energy. The bicycle, being lighter than the car, will have less kinetic energy despite moving at the same speed. Other choices are incorrect because A is false as explained, C is incorrect as the vehicles have different masses, and D is incorrect as both vehicles are in motion, so both have kinetic energy.

Correct Answer: D

Rationale: To find the total voltage in a series circuit, you add the voltages of each battery. In this case, with four 5 V batteries connected in series, the total voltage would be 5 V + 5 V + 5 V + 5 V = 20 V. Therefore, the correct answer is D. Choice A (5.0 V) is incorrect because that would be the voltage of just one battery, not the total voltage of the circuit. Choice B (10.0 V) is incorrect as well since it represents the total voltage of two batteries, not four. Choice C (15.0 V) is also incorrect as it would be the total voltage of three batteries, not four.