HESI Exams Quizlet Physics

Correct Answer: B

Rationale: To find the period of a wave, we use the formula: Period = 1 / Frequency. Given the frequency of 80 vibrations per second, we calculate the period as 1 / 80 = 0.025 seconds. Therefore, choice B (0.025 s) is the correct answer. Choices A, C, and D are incorrect as they do not correctly represent the period calculation based on the given frequency. Choice A (0.0125 s) is half of the correct period, choice C (0.125 s) is ten times greater, and choice D (0.25 s) is incorrect as well.

Correct Answer: C

Rationale: When a charged particle moves through a vacuum at a constant speed, it generates both an electric and magnetic field. This phenomenon is described by Maxwell's equations in electromagnetism. The moving charge creates a changing electric field which, in turn, induces a magnetic field according to Faraday's law of electromagnetic induction. This interplay between electric and magnetic fields is fundamental to electromagnetism. Choice A is incorrect as the moving charge does not only generate an electric field. Choice B is incorrect because the moving charge does not only generate a magnetic field. Choice D is incorrect because a moving charged particle always generates both electric and magnetic fields due to the fundamental principles of electromagnetism.

Correct Answer: B

Rationale: Step-by-step rationale for choice B (Repulsion to magnetic fields) being correct: 1. Diamagnetic materials create small, weak opposing magnetic fields when in the presence of an external magnetic field. 2. These opposing fields cause repulsion between the material and the external field. 3. This repulsion is a characteristic feature of diamagnetism, distinguishing it from other types of magnetism. 4. Therefore, choice B is correct. Summary of why other choices are incorrect: A: Diamagnetic materials are not attracted to magnetic fields, so this choice is incorrect. C: Diamagnetic materials do not amplify magnetic fields, so this choice is incorrect. D: Diamagnetic materials do not show indifference to magnetic fields but rather exhibit repulsion, making this choice incorrect.

Correct Answer: A

Rationale: When you double the distance between two objects, the gravitational force between them decreases by a factor of 4 (inverse square law). So, if the original force was 12 units, when you double the distance, the new force will be 12/4 = 3 units. Therefore, the correct answer is A: 3 units. Summary: - Choice A (3 units) is correct as the force decreases by a factor of 4 when the distance is doubled. - Choices B (6 units), C (24 units), and D (48 units) are incorrect as they do not consider the inverse square law of gravitational force.

Correct Answer: C

Rationale: The correct answer is C: 49 N/cm. To calculate the spring constant, we use Hooke's Law: F = kx, where F is the force applied, k is the spring constant, and x is the displacement from equilibrium. Given F = mg (mass multiplied by gravity) and x = 10 cm = 0.1 m, we can solve for k: k = F/x = mg/x = 5 kg * 9.8 m/s^2 / 0.1 m = 49 N/cm. Choice A is incorrect as it is lower than the correct answer. Choices B and D are incorrect as they are higher than the correct answer.