A Free Body Diagram (FBD) is a helpful way to understand how things move. Here are the main parts:

1. Object of Interest: First, pick the object you want to study. This is often shown as a simple shape, like a box.

2. Forces: Next, draw arrows to show all the forces acting on the object.

   • The length of the arrow shows how strong the force is.
   • The direction of the arrow shows which way the force is pushing or pulling.

   Some common forces are:

   • Gravity (Weight): This force pulls objects down. It is shown with an arrow pointing down, and we calculate it using the formula $W = mg$. Here, $m$ is the mass (how much stuff is in the object) and $g$ is the acceleration due to gravity.
   • Normal Force: This force pushes up against the object from the surface it is resting on. It is shown with an arrow pointing up.
   • Friction: This force tries to stop objects from sliding. It is drawn in the opposite direction of how the object is moving.

3. Net Force: Add up all the forces to find the overall motion. If the net force (total force) is zero, the object is balanced and not moving. If there is a net force, the object will start to speed up or slow down.

Using a Free Body Diagram helps us look at different situations. For example, it can show how a book sits on a table or how a car speeds up. This drawing makes complicated forces easier to understand!