HESI A2
HESI A2 Physics Questions
Question 1 of 5
How do you determine the velocity of a wave?
Correct Answer: A
Rationale: The velocity of a wave can be determined by multiplying the frequency of the wave by the wavelength. This relationship is given by the formula: velocity = frequency wavelength. By multiplying the frequency by the wavelength, you can calculate the speed at which the wave is traveling. This formula is derived from the basic wave equation v = f λ, where v represents velocity, f is frequency, and λ is wavelength.
Therefore, to find the velocity of a wave, one must multiply its frequency by its wavelength.
Choices B, C, and D are incorrect. Adding, subtracting, or dividing the frequency and wavelength does not yield the correct calculation for wave velocity. The correct formula for determining wave velocity is to multiply the frequency by the wavelength.
Question 2 of 5
Surface tension, γ, is a property of fluids arising from:
Correct Answer: A
Rationale: Surface tension, represented by symbol γ, is caused by the cohesive forces between molecules in a liquid. These intermolecular forces, such as Van der Waals forces, hydrogen bonding, and dipole-dipole interactions, create a 'skin' at the surface of the liquid, giving rise to the property of surface tension. Gravitational attraction, viscous dissipation, and pressure differentials within the fluid do not directly contribute to surface tension.
Therefore, the correct answer is A.
Question 3 of 5
Which vehicle has the greatest momentum?
Correct Answer: D
Rationale: The momentum of an object is calculated by multiplying its mass by its velocity. The momentum formula is p = m v, where p is momentum, m is mass, and v is velocity. Comparing the momentum of each vehicle: A: 9,000 kg 3 m/s = 27,000 kg·m/s B: 2,000 kg 24 m/s = 48,000 kg·m/s C: 1,500 kg 29 m/s = 43,500 kg·m/s D: 500 kg 89 m/s = 44,500 kg·m/s.
Therefore, the glider (500-kg) traveling at 89 m/s has the greatest momentum of 44,500 kg·m/s, making it the correct choice. Options A, B, and C have lower momentum values compared to option D, proving that the 500-kg glider traveling at 89 m/s has the highest momentum among the given vehicles.
Question 4 of 5
Two objects attract each other with a gravitational force of 12 units. If you double the mass of both objects, what is the new force of attraction between them?
Correct Answer: C
Rationale: The gravitational force between two objects is directly proportional to the product of their masses. When you double the masses of both objects, the force of attraction between them increases by a factor of 2 x 2 = 4.
Therefore, the new force of attraction between the two objects will be 12 units x 4 = 24 units.
Choices A, B, and D are incorrect because doubling the mass results in a quadruple increase in force, not a linear one.
Question 5 of 5
What characterizes laminar flow?
Correct Answer: A
Rationale: Laminar flow is characterized by the smooth, parallel movement of fluid particles along layers in a predictable manner. This flow regime occurs at low velocities and is in contrast to turbulent flow, where fluid particles exhibit erratic and chaotic motion. The viscosity of the fluid does not hinder laminar flow; instead, it influences the resistance to flow. Incompressibility is a property of fluids but does not specifically define laminar flow.
Therefore, the correct answer is A as it accurately describes the behavior of fluid particles in laminar flow, making B, C, and D incorrect.