HESI A2 Physics Practice Test

Correct Answer: A

Rationale: Rationale: An ideal fluid exhibits zero shear stress at any strain rate. This is because an ideal fluid is assumed to have no resistance to flow, resulting in no shear stress being generated regardless of the strain rate. This is a fundamental characteristic of an ideal fluid and distinguishes it from real fluids that exhibit varying levels of shear stress. Summary: - Choice A is correct as an ideal fluid exhibits zero shear stress at any strain rate. - Choice B is incorrect as it describes a Newtonian fluid which has a linear relationship between shear stress and strain rate. - Choice C is incorrect as it describes a Non-Newtonian fluid with a non-linear relationship between shear stress and strain rate. - Choice D is incorrect as it describes the temperature dependence of viscosity, which is not a defining characteristic of an ideal fluid.

Correct Answer: D

Rationale: Step-by-step rationale: 1. In an isothermal process, temperature remains constant. 2. Compressing a gas increases its pressure. 3. Work is done on the gas by the surroundings in compression. 4. As work is done on the gas, its internal energy decreases. Therefore, choice D is correct. Summary: A: Incorrect; Internal energy does not increase when work is done on the gas. B: Incorrect; Internal energy does not decrease when work is done on the gas. C: Incorrect; Work is done by the surroundings on the gas, not vice versa.

Correct Answer: D

Rationale: Failed to generate a rationale after 5 retries.

Correct Answer: B

Rationale: The correct expression for work (W) is W = F x d. Work is defined as the product of the force applied (F) in the direction of motion and the displacement (d) of the object. Multiplying force by displacement gives the total energy transferred to the object. Option A (W = F / d) is incorrect because dividing force by distance does not represent work. Option C (W = d / F) is incorrect as work is not calculated by dividing distance by force. Option D (W = F^2 x d) is incorrect as squaring the force before multiplying it by displacement is not the correct formula for work. The correct formula for work is the product of force and displacement (W = F x d).

Correct Answer: C

Rationale: The correct answer is C: Identical. When the crane hoists a massive object at a constant velocity, the work done is the same as lifting it gradually because work done is the force applied multiplied by the displacement in the direction of the force. Since the velocity is constant, the force applied remains constant, and the displacement is the same whether lifted gradually or at a constant velocity. Therefore, the work done is identical in both scenarios. Summary: A: Less - Incorrect. The work done is not less when hoisting a massive object at a constant velocity. B: More - Incorrect. The work done is not more when hoisting a massive object at a constant velocity. D: Dependent on the object's mass - Incorrect. The object's mass does not affect the work done in this scenario.