HESI A2 Physics Practice Test

Correct Answer: A

Rationale: To find the period, we use the formula: Period = 1 / Frequency. Given the frequency as 25 beats per second, we calculate 1 / 25 = 0.04 seconds. Therefore, the correct answer is A. Choice B (0.25 s) is incorrect as it represents the inverse of the frequency, not the period. Choice C (0.4 s) and D (4 s) are also incorrect as they are not the correct calculations based on the given frequency.

Correct Answer: B

Rationale: The correct answer is B: The ratio of the potential difference between the ends of a conductor to current is a constant, R. This is in accordance with Ohm's law, which states that V (voltage) = I (current) x R (resistance). Ohm's law establishes a direct proportionality between voltage and current when resistance is constant. The constant R represents the resistance of the conductor. Option A is incorrect because voltage and current are directly proportional when resistance is constant, not inversely proportional. Option C is incorrect as voltage is not the amount of charge passing through a point per second, but rather the potential difference. Option D is incorrect as power is calculated using the formula P = VI, not I x V.

Correct Answer: C

Rationale: The gravitational force between two objects is directly proportional to the product of their masses and inversely proportional to the square of the distance between them (F = G * (m1 * m2) / r^2). When the distance is halved, the force quadruples (2^2 = 4 times). Therefore, if the original force is 12 units, when the distance is halved, the new force will be 12 * 4 = 48 units. Therefore, the correct answer is C. Choice A (3 units) is incorrect because the force increases when the distance is halved. Choice B (6 units) is incorrect as well, as the force should increase more when the distance is halved. Choice D (48 units) is incorrect because the new force of attraction is not doubled but quadrupled when the distance is halved.

Correct Answer: A

Rationale: Rationale: 1. Atoms are electrically neutral, meaning they have no overall charge. 2. Electrons are negatively charged, and protons are positively charged. 3. In a neutral atom, the number of protons equals the number of electrons to balance charges. 4. Therefore, in an electrically neutral atom, the number of electrons is equal to the number of protons (Choice A). Summary: - Choice B is incorrect because protons are not always equal to neutrons in an atom. - Choice C is incorrect as the number of neutrons can vary and is not always greater than protons. - Choice D is incorrect as electrons can be equal to or greater than protons in an atom, depending on the element.

Correct Answer: B

Rationale: The correct answer is B because in a transverse wave, particles of the medium move perpendicular to the direction of energy transfer. Therefore, when the wave moves from north to south, the particles move both northward and southward. Choice A is incorrect because particles don't only move in one direction. Choices C and D are incorrect as transverse waves do not cause particle movement in the east-west direction.