HESI A2 Physics Practice Test

Correct Answer: B

Rationale: Faraday's law of electromagnetic induction states that a changing magnetic field in a conductor induces an electromotive force (EMF) according to the Faraday's law equation. This induced EMF creates a current flow in the conductor. The other choices are incorrect because an increase in resistance (choice A) would oppose the current induced by the changing magnetic field, static electric charge (choice C) is not related to induction, and a decrease in capacitance (choice D) is not directly affected by a changing magnetic field.

Correct Answer: B

Rationale: Step-by-step rationale: 1. Bernoulli's principle states that in a flowing fluid, an increase in flow velocity leads to a decrease in pressure. 2. As the fluid flows faster in a constricted pipe, kinetic energy increases while pressure energy decreases. 3. This relationship between velocity and pressure is consistent for incompressible fluids. 4. Therefore, when the flow velocity increases in a constricted pipe, the pressure will decrease. Summary: - Choice A is incorrect because Bernoulli's principle applies universally to all incompressible fluids. - Choice C is incorrect because pressure changes with velocity according to Bernoulli's principle. - Choice D is incorrect as pressure decreases when velocity increases, as per Bernoulli's principle.

Correct Answer: A

Rationale: Coulomb's law relates to electrostatic interaction. It describes the force between two charged objects based on their charges and the distance between them. It is mathematically represented as F = k*q1*q2/r^2, where F is the force, k is the Coulomb constant, q1 and q2 are the charges, and r is the distance between the charges. This law is fundamental in understanding and calculating the behavior of electrically charged particles. Summary: B: Rigid body motion - unrelated to Coulomb's law. C: Heat conduction - unrelated to Coulomb's law. D: Universal gravitation - Coulomb's law is specific to electric charges, not gravitational forces.

Correct Answer: A

Rationale: To find the period, we use the formula: Period = 1 / Frequency. Given the frequency as 25 beats per second, we calculate 1 / 25 = 0.04 seconds. Therefore, the correct answer is A. Choice B (0.25 s) is incorrect as it represents the inverse of the frequency, not the period. Choice C (0.4 s) and D (4 s) are also incorrect as they are not the correct calculations based on the given frequency.

Correct Answer: D

Rationale: The correct answer is D. Electrons complete a cycle 60 times per second in a 60 Hz household alternating current. This is because the frequency of AC refers to the number of complete cycles per second. Electrons moving back and forth create the alternating current flow. A: Incorrect. The power rating of a bulb (in watts) is determined by the voltage and current, not the frequency. B: Incorrect. The current in household circuits is typically much lower than 60 amperes for safety reasons. C: Incorrect. Voltage drop is dependent on the resistance in the wire and the current flowing, not the frequency of the current.