3 G8 Science Q1-Week 1 of 2Law of Acceleration.pptx

Science 8 Quarter 1 Week 3 Law of Acceleration

1. Law of Inertia Law of Acceleration Law of Interaction PREPARED BY : TYPE YOUR NAME HERE

2. Learning Objectives I can state Newton’s Laws of Motion. I can apply Newton’s Laws of Motion to real life situations. I can describe momentum of different objects and how it affects motion. I can explain the relationship between inertia and mass.

3. Newton ’ s Laws of Motion

4. REVIEW 1. Sir Isaac Newton 2. An object in motion tends to stay in motion and an object at rest tends to stay at rest unless acted upon by an unbalanced force. Inertia is an objects resistance to a change in its motion (even if it isn’t moving at all!) Inertia is caused because objects have mass The more mass an object has, the more inertia!

5. Newton’s Second Law (F = ma) Force equals mass times acceleration. F = ma Acceleration : a measurement of how quickly an object is changing speed.

6. VOCABULARY 1. Force = mass x acceleration F=m x a 2. Force- a push or pull , all forces have size and direction 3. Mass - the amount of matter an object is made of 4. Acceleration -the rate at which velocity changes; and object accelerates if its speed changes, if its direction changes and if both speed and direction changes

7. Newton’s Second Law (F = ma) Force equals mass times acceleration. F = ma

8. More Force = more Acceleration More Mass = more Force needed! Newton’s Second Law of Motion says: “To move a mass, you need a force!” Also known as F=ma I am so smart … The greater the mass = greater inertia = more force needed!

9. Look at the pictures on the right. Which vehicle do you think would require a greater force to push? Why do you think this? Using the equation, solve for the amount of force.

10. Newton’s Second Law (F = ma)

11. Newton’s Second Law (F = ma)

12. Newton’s Second Law (F = ma)

13. #1 1 . A bowling ball rolled with a force of 15 N accelerates at a rate of 3 m/s 2 ; a second ball rolled with the same force accelerates 4 m/s 2 . What are the masses of the two balls? 2.What is the force on a 1000 kg elevator that is falling freely at 9.8 m/s 2 ?

14. Activity # 1 Force and Motion 1. How much force is needed to accelerate a 66 kg skier at 2 m/s 2 ? 2. A force of 20 N acts upon a 5 kg block. Calculate the acceleration of the object. 3. A force of 3.2 N is applied to an object that accelerates at a rate of 3 m/s 2 ? . What is the mass of the object?

15. Drill #1 1. A force of 40 N acts upon a 10 kg block. Calculate the acceleration of the object. A force of 300 N is applied to an object that accelerates at a rate of 15m/s 2 ? . What is the mass of the object? A 50 kg skater pushed by a friend accelerates 5m/s2 . How much force did the friend apply?

16. Activity #:3 1. If a 60 kg person on a 15 kg sled is pushed with a force of 300 N, what will be person’s acceleration? If the force is doubled and the acceleration is 20m/s 2 what will be the result mass?

17. Activity 2 1. How fast will an 800kg car accelerate if it is pushed with 4000N of force? 2. If a 60 kg person on a 15 kg sled is pushed with a force of 300 N, what will be person’s acceleration? 3. A force of 12 N is applied to an object that accelerates at a rate of 3 m/s2? . What is the mass of the object?

18. How fast will an 800kg car accelerate if it is pushed with 4000N of force?

19. How fast will a 0.15kg hockey puck accelerate if it is hit with 1.2 N of force