- #1

- 41

- 0

**1. What is the net force on a cart that is pulled to the right with 100 pounds and to the left with 30 pounds?**

Changes in motion are produced by a force or combination of forces. A force, in the simplest sense is a push or a pull. Its source may be gravitational, electrical, magnetic, or simply a muscular effort. When more than a single force acts on an object, we consider the net force. For example, if you and a friend pull in the same direction with equal forces on an object, the forces combine to produce a net force twice as great as your single force. If each of you pull with equal forces on an object, the forces combine to produce a net force twice as great as your single force. If each of you pull with equal forces in opposite directions the net force is zero. The equal but oppositely directed forces cancel each other. One of the forces can be considered to be the negative of the other, and they add algebraically to zero, with a resulting net force of zero.

A pair of 5 - newton forces in the same direction produce a net force of 10 newtons. If the 5 - newton forces are in opposite directions, the net force is zero. If 10 newtons of force is exerted to the right and 5 newtons to the left, the net force is 5 newtons to the right. The forces are shown by arrows. A quantity such as force that has both magnitude and direction is called a vector quantity. Vector quantities can be represented by arrows whose length and direction show the magnitude and direction of the quantity.

## Homework Equations

**3. 70 newtons to the right**