Understanding Work in Physics

Work, in physics, is done when a force causes an object to move a certain distance. The key is that the force must be in the direction of the movement.

The Scenario

In this case, you're carrying a book at a constant velocity. This means the book's speed isn't changing, and there's no acceleration. Since there's no acceleration, the net force acting on the book is zero.

Why No Work is Done

* Force of Gravity: The book is being pulled down by gravity (2.0 Newtons), but you're applying an equal and opposite upward force to support it. These forces cancel out.

* Force of Motion: You're moving the book horizontally, but the force you're applying is vertically upward. The force of your hand is *perpendicular* to the direction of motion.

Conclusion

Since there is no net force in the direction of motion, no work is done on the book.

Important Note: This is a simplified example. In reality, there would be some minor work done due to friction between the book and your hand, but this is usually negligible.