1. Newton’s Laws and the affects of force
FORCES
Newton’s Laws and the affects of force

2. Forces Unit: newtons (N) Force is a push or a pull that affect matter.
Newton=the force needed to move 1 kg of mass with an acceleration of 1 m/s2

3. Spring Scale Tool used to measure force on an object.
Unit: Newtons (N)

4. Net Forces
Is equal to the number of all forces acting on a single object.

5. Balanced Forces Are equal forces acting in opposite directions.
Produce no change in motion
Ex. Tug of war

6. Unbalanced Forces Produce a change in motion
Ex. Kicking a soccer ball, losing tug of war

7. Centripetal Force
A force that pushes or pulls an object in a circular path.
Ex. Discus thrower’s arm
Video

8. What path will the discus travel when he lets go?
Centripetal Force
What path will the discus travel when he lets go?
Straight path!

9. Three Forces on Objects
The three forces that act on all moving objects are:
1. Gravity
2. Air resistance (wind)
3. Friction

10. Gravity pulls a skier downhill
Gravitational force
The force of attraction that exists between any 2 pieces of matter.
Gravity pulls a skier downhill

11. Universal Law of Gravitation
The force of attraction depends on two things:
1. mass
2. distance

12. Weight versus Mass Which would change when you are on the moon?
Weight! gravity changes based on location.

13. Friction
The force that occurs when 2 surfaces rub together and oppose motion.

14. Types of Friction
Static friction- the force needed to put an object in motion
Fluid friction- gas or liquid that opposes motion.
Sliding friction - sliding an object
Rolling friction - adding wheels to an object

15. Lubricant – a substance that reduces friction. Ex. Oil, water, soap
Friction Video