1 / 23

8 th Grade

8 th Grade. Newton’s Laws of Motion. 5.3 - Forces and Equilibrium ~Background info~. The sum of all the forces acting on an object is called the “net force” (or total force). 5.3 - Forces and Equilibrium.

elu
Download Presentation

8 th Grade

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 8th Grade Newton’s Laws of Motion Jennifer C. Brown

  2. 5.3 - Forces and Equilibrium~Background info~ • The sum of all the forces acting on an object is called the “net force” (or total force). Jennifer C. Brown

  3. 5.3 - Forces and Equilibrium • To figure out if or how an object will move, we look at ALL of the forces acting on it. Jennifer C. Brown

  4. 5.3 - Forces and Equilibrium When several forces act on the same object: • 1. The net force is zero • Or • 2. The net force is NOT zero. Jennifer C. Brown

  5. 5.3 - Forces and Equilibrium • When the forces are balanced, the net force is zero. • When the net force on an object is zero, we say the object is in equilibrium. Jennifer C. Brown

  6. 5.3 - Forces and Equilibrium • What is a normal force? • A normal forceis created whenever an object is in contact with a surface. • The normal force has equal strengthto the force pressing the object into the surface, which is often the object’s weight. Jennifer C. Brown

  7. Newton’s 1st Law of Motion:Law of Inertia • Newton’s first lawsays that objects continue the motion they already have unless they are acted on by a net force. • “An object at rest will stay at rest and an object in motion will stay in motion UNLESS there is a net force to act on it.” • http://teachertube.com/viewVideo.php?title=Newtons_Law_1_on_Inertia&video_id=21642 Jennifer C. Brown

  8. Newton’s 1st Law of Motion:Law of Inertia • Inertia is the property of an object that resists changes in motion. • Objects with more mass have more inertia and are more resistant to changes in their motion. Which ball has more inertia? Jennifer C. Brown

  9. Newton’s 2nd Law of Motion:Force = mass x acceleration • According to Newton’s second law, the amount of acceleration depends on both the force and the mass. F = m x a There are three main ideas related to Newton’s Second Law: Acceleration is the result of unbalanced forces. A larger force makes a larger acceleration. Acceleration is inversely proportional to mass. Jennifer C. Brown

  10. Newton’s 2nd Law of Motion:Force = mass x acceleration The stronger the force on an object, the greater its acceleration. Jennifer C. Brown

  11. Newton’s 2nd Law of Motion:Force = mass x acceleration The greater the mass, the smaller the acceleration for a given force. Jennifer C. Brown

  12. Newton’s 2nd Law of Motion:Force = mass x acceleration • Newton’s Third Law (action-reaction) applies when a force is placed on any object. “For every action, there is an equal and opposite reaction.” Jennifer C. Brown

  13. Newton’s 3rd Law of Motion:action - reaction One force acts on the ball, and the other force acts on the hand. Jennifer C. Brown

  14. Newton’s 3rd Law of Motion:action - reaction You pushing ground The action force is_______________________, and the reaction force is the ______________________________. Ground pushing back on you Jennifer C. Brown

  15. Newton’s 3rd Law of Motion:action - reaction • Newton’s third law tells us that any time two objects hit each other, they exert equal and opposite forces on each other. • The effectof the force is not always the same. Jennifer C. Brown

  16. Newton’s 3rd Law of Motion:action - reaction • Momentum (P) is the mass of an object times its velocity. Jennifer C. Brown

  17. Newton’s 3rd Law of Motion:action - reaction • The law of conservation of momentumstates that as long as the interacting objects are not influenced by outside forces (like friction) the total amount of momentum is constant or does not change. Newton’s Cradle Jennifer C. Brown

  18. Newton’s 3 Laws Rap • http://www.myxer.com/video/id/1979829/ShayiLy/Laws-Of-Motion-Rap/ Jennifer C. Brown

  19. DO NOW: November 21-22, 2011 • Your Name • Objective: • We will review Forces and Newton’s 3 laws of motion. • Homework: Worksheet on applying Newton’s 3 Laws & Notebook Test Next Week (after Break) • Do Now: • 1) What is Newton’s First Law of Motion? • 2) What is Newton’s Second Law of Motion? • 3) What is Newton’s Third Law of Motion? Jennifer C. Brown

  20. DO NOW: November 23, 2011 • Your Name • Objective: • Further review of Forces and Newton’s 3 laws of motion. • Homework: Notebook Test Next Tuesday (after Break)!! • Do Now: • 1) What is the relationship between the mass & the inertia of an object? • 2) If a person pushes on a box at F= 100 N and another person pushes on the same box in the opposite direction at F = 90 N, the resulting force is equal to what? Jennifer C. Brown

  21. Question(s): Two chains are used to support a small boat weighing 1,500 newtons. - One chain has a tension of 600 newtons. - What is the force exerted by the other chain? Jennifer C. Brown

  22. Question(s): Is this object in equilibrium? Yes Jennifer C. Brown

  23. Question(s): A car has a mass of 1,000 kilograms. If a net force of 2,000 N is exerted on the car, what is its acceleration? Jennifer C. Brown

More Related