Unit 2 is about Forces. In this unit, we are going to explore Newton's three laws and their relationships among them. Also, we are going to learn how to draw and interpret the system schemas and force diagrams. After students accomplish all the learning targets and did all the labs in the class, they should be able to do force calculations and solve force problems by using the equations they learned throughout this unit.
Unit 2 Notes
Overview of the content in this unit:
Important Edpuzzle notes:
2.1 Introduction to Inertia and Inertial Mass
2.3 Introduction to Free Body Diagram
Force Diagram / Free Body Diagram
System Schema
Newton's First Law
- Newton’s First Law
- Newton’s Second law
- Newton’s Third Law
- Identifying interactions: System Schemas and Force Diagrams
- Force Calculations
- Solving Force Problems
- Relating Representations of Motion and Force Models
- Solving Problems with Forces and Motion
Important Edpuzzle notes:
2.1 Introduction to Inertia and Inertial Mass
- Inertia: The tendency of an object to resist a change in state of motion.
- Mass: A measure of inertia. A measurement of an object's resistance to acceleration.
- Inertial Mass: A measure of Inertia.
- The more mass, the more inertia, matter and weight.
- Force the ability to cause a change in state of motion of an object.
- More mass added to the mass hanging which increases the force applied to the system.
- More mass added to the sliding block which increases the inertia of the sliding block.
- Force is a vector.
- Contact Force: The two interacting objects touch (apply force).
- Field force: The two interacting objects do not touch (gravity force).
- Diagram will be displayed at the end. (For some reason the image cannot be attached here)
2.3 Introduction to Free Body Diagram
- Center Mass: The location at which we consider all the mass of an object to be concentrated.
Force Diagram / Free Body Diagram
- It shows all the forces acting on an object.
- It also shows the force's direction and its magnitude.
- Diagram will be displayed at the end. (For some reason the image cannot be attached here)
System Schema
- It consists of identifying and labeling all objects of interest from a given physical situation.
- It also shows all the different types of interactions between the objects.
- Diagram will be displayed at the end. (For some reason the image cannot be attached here)
Newton's First Law
- An object will continue to move at a constant velocity unless it feels an unbalanced push or pull.
- Constant Velocity --> Constant speed and constant direction
Newton's Second Law
- An object will continue to move at a constant velocity unless it feels an unbalanced push or pull.
- Acceleration(m/s/s) = Net Force(N) / Mass(kg) --> a = ∑F / m
- As the equation shows, the acceleration is directly proportional to total force and inversely proportional to total mass.
Newton's Third Law
- Whenever two objects interact, each object exerts an equal force on the OTHER object. These forces are equal in magnitude but opposite in direction.
- When an object (Object A) exerts any force on another object (Object B), the third law pair according to Newton's 3rd Law is:
- Exerted BY the object receiving the original force (Object B)
- Exerted ON the object applying the original force (Object A)
- The same type of force/interaction as the original
- Two forces that are third law pairs will NEVER appear on the same force diagram.
- eg. Fg by Earth on a person
- Fg by a person on Earth
Conclusion of Newton's Three Law and their relationships
- In summary, Newton's laws boil down to F=ma . An enormous quantity of physical science has been developed by applying this simpleB.1 mathematical law to different physical situations.
- All three of Newton's laws work together to help describe how an object will move.
Types of Forces
Force Calculations
Solving Force Problems
Relating Representations of motion and Force Models
Widget is loading comments...