HESI A2
HESI Exams Quizlet Physics Questions
Question 1 of 5
The specific heat capacity (c) of a material is the amount of heat transfer (Q) required to raise the temperature (ΔT) of a unit mass (m) of the material by one degree (typically Celsius). The relationship between these quantities is described by the equation:
Correct Answer: A
Rationale: The correct equation relating heat transfer (Q), mass (m), specific heat capacity (c), and change in temperature (ΔT) is Q = mcΔT. This equation states that the heat transfer is equal to the product of the mass, specific heat capacity, and temperature change.
Therefore, the correct answer is B, as it correctly represents this relationship.
Choices C and D do not correctly represent the relationship between these quantities and are therefore incorrect.
Question 2 of 5
An object moves 100 m in 10 s. What is the velocity of the object over this time?
Correct Answer: A
Rationale: Velocity is calculated as the displacement divided by the time taken to cover that displacement. In this case, the object moves 100 meters in 10 seconds.
Therefore, the velocity is 100 m / 10 s = 10 m/s.
Choice B, 90 m/s, is incorrect as it doesn't match the calculated velocity.
Choice C, 110 m/s, is incorrect as it is higher than the calculated velocity.
Choice D, 1,000 m/s, is incorrect as it is significantly higher than the calculated velocity.
Question 3 of 5
What is the main difference between a reversible and irreversible process in thermodynamics?
Correct Answer: C
Rationale: A reversible process is an idealized process that can be reversed without leaving any change in either the system or the surroundings. In contrast, irreversible processes cannot be reversed and often involve entropy production or dissipation.
Choice A is incorrect because both reversible and irreversible processes can involve heat transfer.
Choice B is incorrect as the speed of a process does not determine its reversibility.
Choice D is incorrect because reversible processes do not violate the first law of thermodynamics; they comply with it by maintaining a balance between energy inputs and outputs.
Therefore, the correct answer is C, as it accurately captures the main difference between reversible and irreversible processes in thermodynamics.
Question 4 of 5
Diamagnetism refers to a material's weak:
Correct Answer: B
Rationale: Diamagnetism refers to a material's weak repulsion to magnetic fields. When diamagnetic materials are placed in an external magnetic field, they create an opposing magnetic field, leading to repulsion. This is why choice B, 'Repulsion to magnetic fields,' is the correct answer.
Choices A, C, and D are incorrect because diamagnetic materials do not exhibit attraction, amplification, or indifference to magnetic fields.
Question 5 of 5
The drag force (F_d) experienced by an object moving through a fluid depends on:
Correct Answer: B
Rationale: The drag force experienced by an object moving through a fluid depends on multiple factors, including the object's shape, size, velocity, and the fluid's properties such as viscosity and density.
Choices A, C, and D are incorrect because drag force is not solely determined by the object's shape and size, depth of submersion, or buoyant force acting on the object. The primary factors affecting drag force are the fluid properties and the object's velocity.
Therefore, the correct answer is B.