HESI A2 Physics

Correct Answer: D

Rationale: To find amperes, use the formula: Power (W) = Voltage (V) x Current (I) Given: P = 1525W, V = 110V Therefore, I = P / V = 1525W / 110V = 13.8636A ≈ 13.9 amperes (option D). Explanation: The correct answer is D because it correctly calculates the amperes drawn by the hair dryer using the power and voltage values provided. Option A is too high, B and C are too low.

Correct Answer: C

Rationale: Step 1: A negative heat of reaction indicates that energy is released during the reaction. Step 2: Since energy is released, the products have lower energy compared to the reactants. Step 3: Lower energy in products means they are more stable. Therefore, the correct answer is C: The products have less energy and are more stable. Summary: A: Incorrect. Products have lower energy and are more stable, not less stable. B: Incorrect. Products have lower energy and are more stable, not more stable. D: Incorrect. Products have lower energy and are more stable, not less stable.

Correct Answer: A

Rationale: Surface tension is caused by the cohesive forces between molecules in a fluid, which are the intermolecular forces. These forces create an imbalance at the surface, resulting in the phenomenon of surface tension. Gravitational attraction (B) is not the primary cause of surface tension, viscous dissipation (C) is related to fluid flow resistance, and pressure differentials (D) within the fluid do not directly cause surface tension. Therefore, the correct answer is A.

Correct Answer: D

Rationale: The correct answer is D because salt increases the density of water, making it more buoyant. Higher water density provides greater buoyant force on the boat, allowing it to float more easily. Choices A, B, and C are incorrect as salt does not directly affect the mass of the boat, the volume of water, or the density of the boat itself.

Correct Answer: D

Rationale: To find the total voltage in a series circuit, you add the voltages of each battery. In this case, with four 5 V batteries connected in series, the total voltage would be 5 V + 5 V + 5 V + 5 V = 20 V. Therefore, the correct answer is D. Choice A (5.0 V) is incorrect because that would be the voltage of just one battery, not the total voltage of the circuit. Choice B (10.0 V) is incorrect as well since it represents the total voltage of two batteries, not four. Choice C (15.0 V) is also incorrect as it would be the total voltage of three batteries, not four.