1. Unit 2 - Forces

2. Types of Forces In this chapter we will explore; Different types of forces and learn about how they affect the velocity and acceleration of objects. Newton’s Three Laws of motion to explain how and why objects move. Free-body Diagrams to calculate net force and acceleration. Problem solving related forces and motion in one dimension.

3. Forces Our previous unit of kinematics focused on how objects move without being concerned with why they move. In our next unit of study we will concentrate on why an object moves by looking at the various forces acting on it. Forces can cause objects to change their motion. Dynamics is the study of the causes of motion.

4. 3.1 Types of Forces A system diagram is a simple sketch showing all the objects involved in a scenario. For example, two children pulling on a wagon. A free-body diagram (FBD) is a simple drawing of an object showing all the forces that are acting on it. The forces acting on the wagon.

5. 3.1 Everyday Forces

7. 3.1 Four Fundamental Forces Physicists have grouped all known natural forces into four categories: Gravitational forces are attractive and exist between any two masses in the universe. Unnoticeable between two small masses compared to Earth’s gravity. Electromagnetic forces are caused by electric charges and magnets. This force can both attract and repel. Strong Nuclear forces are attractive between the protons and neutrons within the nucleus of an atom, preventing the protons from repelling one another and flying apart. Weak Nuclear forces are responsible for transforming protons ad neutrons into other particles during nuclear reactions.

8. 3.1 Homework Practice # 2 p.119 Practice # 1-3 p.120 Questions # 2, 5, 7, 10, 13, 15 p.122