Final answer:
Auto-boxing can work inside arithmetic expressions in Java, where primitive data types are automatically converted to their corresponding wrapper classes. The correct answer is option is 3 .
Step-by-step explanation:
When discussing work within the realm of physics, it's essential to differentiate between work done on the system and work done by the system. The notion of work relates to the force applied to an object and the displacement of that object in the direction of the force. Work is a form of energy transfer, and therefore, it's vital to be precise regarding the direction of that transfer when performing calculations.
Work done on the system refers to energy that is transferred to the system from its surroundings. This can increase the system's energy. On the other hand, work done by the system describes the energy that the system transfers to its surroundings. This typically results in a decrease in the system's energy. Being careful with these terms is crucial because they have opposite effects on the system's energy and can significantly alter the outcomes of your calculations. Differentiating them ensures conservation of energy is appropriately applied.
When assembling a system of point charges, it's important to understand that the order in which the charges are assembled does not affect the total work done. This is because work is a scalar quantity—it only has magnitude and no direction. The total work done in assembling point charges is dependent on the final configuration of charges and not the path taken to reach that configuration. This principle is in line with the concept of conservative forces in physics, where the work done by or against such a force is path-independent.
Whether dealing with electric charges or any objects in a conservative field, the total work done only depends on the initial and final states of the system. This is the reason why gravitational force is also considered a conservative force—the work done moving a mass in a gravitational field depends only on the differences in potential energy, regardless of the path taken between two points.