HESI A2 Physics

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.

Correct Answer: D

Rationale: To calculate work, we use the formula W = F*d, where W is work, F is force, and d is distance. In this case, the force is 15 N and the distance is 3 m. So, W = 15 N * 3 m = 45 N⋅m. Therefore, the correct answer is D. Choice A is incorrect as it incorrectly calculates work by dividing force by distance. Choice B is incorrect as it only provides the correct unit for work, not the actual calculation. Choice C is incorrect as it incorrectly multiplies force and distance to get the wrong result.

Correct Answer: C

Rationale: The correct answer is C: Hydrogen gas. This is because gases are highly affected by changes in temperature due to their particles having more kinetic energy. When temperature increases, gas particles move faster, increasing pressure. Conversely, when temperature decreases, gas particles move slower, decreasing pressure. In contrast, liquid nitrogen (choice A) and salt crystals (choice B) are not as affected by temperature changes due to their stable structures. Iron filings (choice D) are also not significantly affected by temperature changes as they are solid and have a fixed shape and volume.

Correct Answer: D

Rationale: The correct answer is D: Kinetic energy. Potential energy is the energy stored in an object due to its position or state. As the vehicle rolls downhill, potential energy decreases while kinetic energy, the energy of motion, increases. This transformation occurs as the vehicle gains speed and moves due to the force of gravity. The other choices are incorrect because thermal energy is not directly related to the motion of the vehicle in this scenario, and the transformation does not involve a combination of thermal and kinetic energy. The vehicle's movement downhill is primarily a conversion of potential energy into kinetic energy.

Correct Answer: A

Rationale: The correct answer is A: Pressure. Pumps increase fluid pressure by adding energy to the fluid. When the fluid flows through the pump, it gains kinetic energy which is then converted into pressure energy. Choice B is incorrect because pumps do not primarily aim to increase velocity only. Choice C is incorrect as while pumps do increase both pressure and velocity, the primary goal is to increase pressure. Choice D is incorrect as pumps are specifically designed to increase either pressure, velocity, or both, depending on the application.