HESI Exams Quizlet Physics

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.

Correct Answer: C

Rationale: The correct answer is C because reversible processes can be run in both directions with the same outcome, while irreversible processes cannot. In a reversible process, the system and surroundings can be restored to their original states after the process is reversed, maintaining equilibrium. This is not possible in irreversible processes, where energy dissipation and entropy generation lead to permanent changes. Choices A, B, and D are incorrect because reversible processes can involve heat transfer, do take time, and do not violate the first law of thermodynamics.

Correct Answer: A

Rationale: The momentum of an object is calculated by multiplying its mass by its velocity. In this case, for option A, the momentum of the car is calculated as 1,250 kg x 5 m/s = 6,250 kg*m/s. This is greater than the momentum of the other choices. For option B, the momentum of the person is 80 kg x 4 m/s = 320 kg*m/s, which is less than the car's momentum. For option C, the momentum of the meteorite is 10 kg x 600 m/s = 6,000 kg*m/s, which is also less than the car's momentum. For option D, the momentum of the rock is 0.5 kg x 40 m/s = 20 kg*m/s, making it the smallest momentum among the choices. Therefore, the car moving at 5 m/s has the greatest momentum due to its higher mass and velocity compared to the other objects.

Correct Answer: D

Rationale: The correct answer is D: To allow the circuit to open and close. A switch in a circuit functions by either completing or interrupting the flow of current. When the switch is closed, it provides a path for the current to flow, allowing the circuit to be operational. Conversely, when the switch is opened, it breaks the circuit, halting the flow of current. This on-off capability of a switch enables control over the circuit, making it a fundamental component in regulating the flow of electricity. Choices A, B, and C are incorrect because a switch does not reverse the direction of current, increase voltage, or alter the resistance of wires in a circuit.