Forces…
change the motion of objects in predictable ways.
Forces change motion
Now you will learn: What a force is
How unbalanced forces change motion
Newton’s first law
ForceA force is a push or a
pull
Types of Forces (3)
1. Contact force When one object pushes or pulls by touching
another object, the first object is applying a contact force to the second
Types of Forces
2. Gravity The force of attraction between two masses
Types of Forces
3. Friction A force that resists motion
Net Force
Overall force acting on an object
- A net force of 0 is balanced
- Motion does not change
Net Force
Unbalanced forces - Change motion
Newton’s First Law
Things keep doing what they’re doing
Objects at rest remain at rest, and objects in motion remain in motion with the same velocity, unless acted upon by an unbalanced force
Inertia Is it easier to push or pull a full shopping cart or an
empty one?
Inertia – resistance of an object to change the direction or speed of its
motion
Summary
Force- a push or a pullNet force- balanced and unbalanced3 types of forces Contact, Gravity, FrictionNewton’s first lawInertia