1. Force Dayna Lee Martínez STARS - USF Maniscalco Elementary

2. What is a force? A force is a push or pull that causes an object to move, stop, or change direction

3. What is friction? Push Friction

4. What is friction? Pull of the horse Friction

5. What is friction? A force that opposes motion Friction can make things slow down or stop, or it can keep things from moving at all Friction is present whenever surfaces touch Friction is greater between rough surfaces than between smooth ones Friction changes energy of motion to heat as objects rub together

6. What is gravity? Gravity is the force of attraction between objects Gravity causes falling objects to speed up as they fall

7. Gravitational Force The pull of all objects in the universe on one another Depends on the mass and the distance between the objects The greater the mass and the closer they are, greater the gravitational force between them

8. Gravitational force Which one will pull objects towards it’s center with more force, the Earth or the Moon? Why?

9. Weight Weight is the measurement of gravitational force acting on an object Will a person weigh more on Earth or in the moon? Where the mass would be greater?

10. Magnetic and Magnetic Force An object that attracts iron and certain other materials such as steel is magnetic The force exerted by a magnet is called magnetic force

11. Magnetic Force

12. On a Roll Lab Manual, page 64