HESI A2 Physics

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: C

Rationale: During adiabatic compression, no heat is exchanged with the surroundings, so the internal energy of the gas is increased, leading to an increase in temperature (Choice C). Adiabatic compression is an inherently exothermic process due to the work done on the gas. Choice A is incorrect because temperature is directly related to the internal energy of the gas, not heat exchange. Choice B is incorrect as compression of a gas leads to an increase in temperature, not a decrease. Choice D is incorrect as the behavior of a gas during adiabatic compression can be predicted based on the laws of thermodynamics.

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: A

Rationale: To calculate the magnitude of the resulting force, we use Coulomb's Law: F = k * |q1 * q2| / r^2, where k is the electrostatic constant (8.99 x 10^9 N m^2/C^2), q1 and q2 are the charges, and r is the distance between them. Plugging in the values: F = (8.99 x 10^9) * |4 x 10^-6 * 2 x 10^-6| / 1^2 = 0.072 N. However, the question asks for the magnitude, so the answer should be 0.072 N, which corresponds to choice B. The other choices are incorrect because they do not correctly calculate the force using Coulomb's Law or misinterpret the question.

Correct Answer: C

Rationale: To find the image distance using the mirror formula (1/f = 1/v + 1/u), we first need to calculate the object distance (u). Given the object distance (u) is 20 cm, and the focal length (f) is 10 cm, we can substitute these values into the formula to find the image distance (v). Solving for v, we get v = 60 cm. Therefore, the correct answer is C: 60 cm. Choice A (20 cm) is incorrect as the image distance is not equal to the object distance when using a concave mirror. Choice B (40 cm) is incorrect as it does not account for the focal length of the mirror. Choice D (75 cm) is incorrect as it is not the result of the correct calculation using the mirror formula.