1. Newton’s Second Law

2. Objective ► At the end of today, you will be able to explain:  The greater the force exerted on the object, the greater the acceleration.  For any force, the greater the mass of an object, the smaller the acceleration. ► And the smaller the mass, the larger the acceleration.

3. Newton’s Second Law Newton's 2nd Law Animation

4. Newton’s 2 nd Law ► Shopping Cart Simulation-  What happens when more force is added to an object with the same mass?  What happens to the acceleration when the same force is applied to a larger mass?

5. What is the relationship between force and acceleration? ► The harder you push or pull something, the faster it will accelerate. ► Force and acceleration are directly proportional.  This means whatever happens to one quantity happens to the other.

6. What is the relationship between mass and acceleration? ► As the Mass goes up ► ► The Acceleration goes down

7. What is the relationship between mass and acceleration? ► Mass and acceleration are inversely proportional. ► That means if one increases, the other decreases.

8. Zero Net Force ► If there is zero net force, then a = 0.  F = ma ► However, an object can be moving even if there is zero net force on the object.  It is moving with a constant velocity ► Constant speed and constant direction (straight line) ► Velocity remains the same if there is no acceleration.

9. How does this picture demonstrate Newton’s 2nd Law?

10. Exit Ticket ► Johnny and Peggy Sue are each going to push a 25 kg weight plate. Johnny is going to apply a force of 50 N, and Peggy Sue is going to apply a force of 100 N. What is each person’s acceleration? Is there a difference between their accelerations? If so, explain why they are different. ► Remember: a=F / m

11. Resources ► http://galileo.phys.virginia.edu/outreach/8thgradesol/Newtons2.htm http://galileo.phys.virginia.edu/outreach/8thgradesol/Newtons2.htm ► http://www.classzone.com/books/ml_science_share/vis_sim/mfm05_pg50_newton/mfm05_pg50_newton.html http://www.classzone.com/books/ml_science_share/vis_sim/mfm05_pg50_newton/mfm05_pg50_newton.html ► http://www.astronomynotes.com/gravappl/s2.htm#A1.2 http://www.astronomynotes.com/gravappl/s2.htm#A1.2 ► http://www.bbc.co.uk/scotland/learning/bitesize/standard/physics/transport/forces_at_work_rev6.shtml http://www.bbc.co.uk/scotland/learning/bitesize/standard/physics/transport/forces_at_work_rev6.shtml