1. Types of Structures: it defines whether it is a shell , solid, frame or combination.
1.1. The human body: is a combination of all three of the other forms. The frame is the skeleton. The stomach is an example of a shell. Our brains are an example of a solid structure.
1.2. Milk carton: It is a shell structure. Shell structures are usually used to contain, in this case, it contains milk. We know it is a shell structure because it is hollow and has no holes.
2. Form and Functions
2.1. Functions: it is what the structure is designed to do.
2.1.1. Bridge: A bridge helps hold people,cars, trucks and etc.
2.1.1.1. when a car drives on the bridge that causes the bridge to hold more weight up.
2.1.2. A cup:A is to help hold liquid like coffee, music and etc
2.1.2.1. when liquid is poured into the cup that causes the cup to hold to liquid in place so it doesn't spill.
2.2. Form: it is how a structure appears.
3. Internal Forces
3.1. An internal force makes a structure change shape. Internal forces happen because of external forces.
3.1.1. When a person applies an external force by stretching a rubber band, they create tension, something stretched.
3.2. There are four types of internal forces.
3.2.1. Shear is when a structure breaks from receeiving pressure in different places.
3.2.1.1. Same with the branch.
3.2.2. Torsion is when the structure twists.
3.2.2.1. The skater spins and creates torsion: external to internal
3.2.3. Compression is when a structure gets squeezed.
3.2.3.1. The soccer ball gets compressed. The ground and the foot pushes/pulls it.
3.2.4. Tension is when a structure stretches.
3.2.4.1. This person stretches their musselss.
4. External Forces
4.1. An external force is a force from the outside of the structure.
4.1.1. The result depends on four factors: the magnitude, point of application, the plane of application, and the direction.
4.1.1.1. The magnitude determines how strong the force is.
4.1.1.1.1. A poke is a weak force.
4.1.1.2. The direction determines which way an object is applied. Wether it is a push away from the applier of the force or a pull, vice versa.
4.1.1.2.1. You can pull an object to yourself, like keeper hugging a ball.
4.1.1.3. The plane of application determines the angle at which the force is applied, primarily 180, 90, or 45 degrees.
4.1.1.3.1. These cars crash head to head.
4.1.1.4. The point of applicaton is how high or low the force is applied.
4.1.1.4.1. Pushing the top of the box will have different results.