Nokea
In a scenario where a transverse wave transports energy from north to south, in what direction do the particles in the medium move?
- A. Only north to south
- B. Both northward and southward
- C. Only east to west
- D. Both eastward and westward
Correct Answer: B
Rationale: In a transverse wave, particles of the medium move perpendicular to the direction of energy transport. When the wave transports energy from north to south, the particles in the medium oscillate up and down, causing them to move both northward and southward. Choice A is incorrect because the particles move in both directions, not only from north to south. Choices C and D are incorrect as they mention directions that are not relevant to the scenario described in the question.
You may also like to solve these questions
If a 5-kg ball is moving at 5 m/s, what is its momentum?
- A. 10 kgâ‹…m/s
- B. 16.2 km/h
- C. 24.75 kgâ‹…m/s
- D. 25 kgâ‹…m/s
Correct Answer: D
Rationale: The momentum of an object is calculated by multiplying its mass by its velocity. In this case, the mass of the ball is 5 kg and its velocity is 5 m/s. Therefore, the momentum of the ball is 5 kg 5 m/s = 25 kgâ‹…m/s. Choice A (10 kgâ‹…m/s) is incorrect as it does not account for both mass and velocity. Choice B (16.2 km/h) is incorrect as it provides a speed in a different unit without considering mass. Choice C (24.75 kgâ‹…m/s) is incorrect as it does not correctly calculate the momentum based on the given mass and velocity.
When a crane hoists a massive object at a constant velocity compared to lifting the same object gradually, the work done by the crane is:
- A. Less
- B. More
- C. Identical
- D. Dependent on the object's mass
Correct Answer: C
Rationale: The work done by the crane is identical in both scenarios. Work is defined as the force applied over a distance. Since the force needed to lift the object is equal to its weight and the displacement is the same, the work done is identical, whether the object is lifted gradually or at a constant velocity. Choice A is incorrect because the work done is the same in both cases. Choice B is incorrect as well since the work done does not increase. Choice D is incorrect as the mass of the object does not affect the work done by the crane in this scenario.
An object with a charge of 3 μC is placed 30 cm from another object with a charge of 2 μC. What is the magnitude of the resulting force between the objects?
- A. 0.6 N
- B. 0.18 N
- C. 180 N
- D. 9 10−12 N
Correct Answer: B
Rationale: To find the magnitude of the resulting force between two charges, we use Coulomb's Law:
F = k (|q1 q2|) / r²
Where:
F is the force
k is Coulomb's constant (8.99 10â¹ N·m²/C²)
q1 and q2 are the charges
r is the distance between the charges
Plugging in the values:
F = (8.99 10â¹) (3 10â»â¶) (2 10â»â¶) / (0.3)² = 0.18 N.
Therefore, the magnitude of the resulting force is 0.18 N.
When analyzing a power plant, which of the following is NOT considered a part of the system?
- A. The fuel being burned.
- B. The working fluid (e.g., steam or water).
- C. The turbine that generates electricity.
- D. The surrounding air.
Correct Answer: D
Rationale: In a power plant system, the components directly involved in the energy conversion process are considered part of the system. The fuel being burned provides the heat source, the working fluid transfers this heat energy, and the turbine converts it into mechanical energy to generate electricity. The surrounding air, while it may interact with the system, is not a component that directly participates in the energy conversion process within the power plant system. Therefore, the correct answer is D - The surrounding air. Choices A, B, and C are essential components of a power plant system as they play direct roles in the energy conversion process, unlike the surrounding air.
The specific heat capacity of tin is 217 J/(g°C). Which of these materials would require about twice as much heat as tin to increase the temperature of a sample by 1°C?
- A. Copper [0.3844 J/(g°C)]
- B. Iron [0.449 J/(g°C)]
- C. Gold [0.1291 J/(g°C)]
- D. Aluminum [0.904 J/(g°C)]
Correct Answer: D
Rationale: The correct answer is D: Aluminum. The specific heat capacity of aluminum is 0.904 J/(g°C), which is approximately 4 times that of tin. For a material to require about twice as much heat as tin to increase the temperature by 1°C, it should have a specific heat capacity roughly double that of tin. Therefore, aluminum fits this criterion better than the other options. Gold has a much lower specific heat capacity than tin, so it would require less, not more, heat to increase the temperature by 1°C. Copper and Iron also have specific heat capacities lower than tin, making them incorrect choices for requiring twice as much heat as tin.