HESI Exams Quizlet Physics

Correct Answer: A

Rationale: Semiconductors fall between conductors and insulators in terms of electrical conductivity because they have conductivity levels higher than insulators but lower than conductors. Conductors have high conductivity due to abundant free electrons, while insulators have very low conductivity due to the lack of free electrons. Semiconductors can conduct electricity under certain conditions by manipulating the number of free electrons through doping or applying electric fields. Therefore, choice A is correct. Choices B, C, and D are incorrect because they do not accurately represent the conductivity levels of semiconductors in relation to other materials.

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: C

Rationale: To find the frequency of the wave, we use the formula: speed = wavelength x frequency. Given speed = 20 m/s and wavelength = 4 m, we rearrange the formula to solve for frequency: frequency = speed / wavelength = 20 m/s / 4 m = 5 Hz. Therefore, the correct answer is C: 24 s^-1. Choice A is incorrect as it does not match the calculated frequency. Choices B and D are also incorrect as they do not align with the calculated frequency based on the given information.

Correct Answer: B

Rationale: Sure! Pascal's principle states that a pressure change applied to a confined incompressible fluid is transmitted undiminished throughout the fluid. This is because the fluid transmits the pressure equally in all directions. The other choices are incorrect because: A: Pressure is not amplified, it remains constant. C: The pressure change is not limited by the container size. D: The fluid type may affect other properties, but not the transmission of pressure.

Correct Answer: A

Rationale: To find the current flowing through the flashlight, use Ohm's Law: Current (I) = Voltage (V) / Resistance (R). Given V=3V and R=60Ω, I = 3V / 60Ω = 0.05 amp (A). This is the correct answer. Choice B, 0.5 amp, is incorrect as it does not match the calculated value. Choice C and D, 1.8 amp and 18 amp respectively, are also incorrect as they are significantly higher than the calculated current value and would require a much higher voltage source.