HESI A2
HESI Exams Quizlet Physics Questions
Question 1 of 5
For the core of an electromagnet, a material with high:
Correct Answer: B
Rationale: A material with high permeability is preferred for the core of an electromagnet because it allows magnetic field lines to pass through it easily, enhancing the strength of the magnetic field generated.
Choice A is incorrect because high resistivity would impede the flow of current in the coil, reducing the strength of the magnetic field.
Choice C is incorrect as permittivity is related to electric fields, not magnetic fields.
Choice D is also incorrect because dielectric strength is about insulating materials against breakdown under an electric field, not relevant to enhancing magnetic fields.
Question 2 of 5
Given the four wires described here, which would you expect to have the greatest resistance?
Correct Answer: D
Rationale: The wire with the greatest resistance is the one with the smallest diameter, as resistance is inversely proportional to cross-sectional area. Gauge 4 with a 5.19 mm diameter has the smallest diameter and, therefore, the greatest resistance.
Choice A, B, and C have larger diameters compared to choice D, so they would have lower resistance values.
Question 3 of 5
Which characteristic does a transverse wave not have?
Correct Answer: A
Rationale: A transverse wave does not have a compression because transverse waves move perpendicular to the direction of the oscillation. In a transverse wave, the particles move up and down, causing crests and troughs, without creating compressions. Compressions are characteristic of longitudinal waves where the particles move parallel to the direction of the wave. The other choices (B, C, and
D) are characteristics that transverse waves possess: amplitude is the maximum displacement of a wave from its equilibrium position, frequency is the number of complete oscillations a wave makes in a given time, and wavelength is the distance between two consecutive points in a wave that are in the same phase.
Question 4 of 5
In terms of electrical conductivity, semiconductors fall between
Correct Answer: A
Rationale: Semiconductors have electrical conductivities that lie between those of conductors (high conductivity) and insulators (low conductivity). This positioning makes choice A, 'Conductors and insulators,' the correct answer.
Choice B, 'Conductors and superconductors,' is incorrect because superconductors have perfect conductivity, not intermediate like semiconductors.
Choice C, 'Insulators and dielectrics,' is incorrect because dielectrics are a type of insulator, so it doesn't show the progression from high to low conductivity.
Choice D, 'Superconductors and insulators,' is incorrect because superconductors have the highest conductivity, opposite to the role of semiconductors.
Question 5 of 5
A wave moves through its medium at 20 m/s with a wavelength of 4 m. What is the frequency of the wave?
Correct Answer: C
Rationale: The formula to calculate the frequency of a wave is given by: