HESI A2 Physics

Correct Answer: A

Rationale: To determine the velocity of a wave, you need to use the formula v = fλ, where v is the velocity, f is the frequency, and λ is the wavelength. By multiplying the frequency by the wavelength (option A), you are essentially applying the correct formula for calculating wave velocity. This is because the velocity of a wave is directly proportional to both its frequency and wavelength. Option B (adding the frequency and wavelength) and Option C (subtracting the wavelength from the frequency) do not align with the correct formula for wave velocity calculation, as it involves multiplication rather than addition or subtraction. Option D (dividing the wavelength by the frequency) is also incorrect because the correct operation for determining wave velocity is multiplication, not division.

Correct Answer: C

Rationale: Failed to generate a rationale after 5 retries.

Correct Answer: B

Rationale: The correct answer is B: Conduction. When the hot cup of coffee is placed on a cold table, heat transfer primarily occurs through conduction. This is because heat is transferred from the hot coffee to the cold table through direct contact. Conduction is the process of heat transfer through a material due to direct molecular collisions. Radiation (choice A) involves the transfer of heat through electromagnetic waves, which is not the primary process in this scenario. Convection within the coffee (choice C) involves the transfer of heat through the movement of fluid particles, but in this case, the primary heat transfer mechanism is conduction. Choice D is incorrect as it suggests a combination of conduction and convection, when conduction is the dominant process in this situation.

Correct Answer: B

Rationale: To find the radius of the circular track, we use the formula: circumference = 2 * π * radius. Given circumference = 2,500m, we can rearrange the formula to solve for radius: radius = circumference / (2 * π) = 2,500 / (2 * 3.14) ≈ 398.73m. Therefore, the closest option to the calculated radius is B: 400m. Incorrect answers: A: 1,000m - This is twice the correct radius, not accurate. C: 25m - This is 10 times smaller than the correct radius, not accurate. D: 12m - This is much smaller than the correct radius, not accurate.

Correct Answer: A

Rationale: The correct answer is A: 5 miles per hour due southwest. A vector quantity has both magnitude and direction, which is represented by the speed (5 miles per hour) and the direction (southwest). This choice clearly indicates both aspects. Explanation for why the other choices are incorrect: - B: 5 miles per hour: This choice only provides the magnitude of the quantity (speed) without indicating any direction. - C: 5 miles: This choice only provides the magnitude (distance) without any indication of direction. - D: None of the above: This choice dismisses all options without providing the correct representation of a vector quantity with both magnitude and direction.