Forces Basics
What is a force?
A push or a pull
What happens when forces are unbalanced?
There is motion
What is friction?
A force that opposes motion
Which law says objects stay at rest or in motion unless acted on by a force?
Newton’s 1st Law
What is momentum?
How difficult it is to stop a moving object
What is the unit used to measure force?
Newtons
What happens when forces are balanced?
There is no motion
Does friction speed objects up or slow them down?
Slow them down
What is inertia?
An object’s resistance to a change in motion
Which object has more inertia: large or small?
Larger
What is net force?
All of the combined forces acting on an object
If two forces of 10 N push in opposite directions, what is the net force?
0 N
Name one cause of friction.
Bumps and dips on surfaces OR weak electrical charges
Which law explains the relationship between force, mass, and acceleration?
Newton’s 2nd Law
Which object has more momentum?
The larger and faster-moving object
When forces act in the same direction, what do you do to find the net force?
Add them
Gravity pulling objects toward Earth is an example of what type of force?
Noncontact force
Friction works with motion or against motion?
Against motion
Which law says every action has an equal and opposite reaction?
Newton’s 3rd Law
What two things affect momentum?
Mass and speed
When forces act in opposite directions, what do you do to find the net force?
Subtract them
Name one noncontact force.
Gravity (or magnetic force)
Which surface would have more friction: rough or smooth?
Rough
Why don’t action-reaction force pairs cancel each other out?
They act on different objects
Give an example of an action-reaction force pair.
Many possible answers (ex: pushing a wall, jumping off the ground)