What is a force?
A push or a pull
True or false: Friction can only happen when two solids objects are touching.
FALSE - friction can occur between liquids and gases too!
What is net force?
The sum of all the forces acting on an object
airplanes flying, parachute slowing down, paper floating back and forth as it falls
True or false: Gravity is stronger on the moon than it is on earth.
False
What is a contact force?
What is friction?
A contact force that slows down objects when they rub against each other
When multiple forces acting on an object are in the SAME direction, how do you calculate the net force?
Add forces together
What is a type of contact force? (be specific)
Normal, applied
As distance between two objects increases, the force of gravity _______________________
Name a type of noncontact force
Gravity, electric, or magnetism
Which surface will have more friction: a smooth counter top OR a gravel road?
A gravel road - it is bumpier and will have more friction
What is the net force?
What is 0 Newtons?
You and your dad are moving the couch from one side to another. Your dad pushes with a force of 35 N to the right and you push with a force of 25 N right. What is the net force on the couch?
60 N right
DOUBLE JEOPARDY:
In the following experiment, what is the independent variable?
How does the size of the magnet effect how strong the magnet pulls?
the size of the magnet ("I" the scientist decide what size magnet to use)
What is an example of a normal force?
One object sitting or being supported by another object
If an object is not moving, are the forces acting on it balanced or unbalanced?
Balanced
If opposing forces acting on an object are equal, what is the net force?
0 N
Below is an electromagnet, which is a type of temporary magnet. What are the 2 forces that allow this device to work?
electric and magnetic
DOUBLE JEOPARDY: Why do you weigh less on the moon than on earth?
there is less gravity on the moon because the moon has less MASS than earth
As mass increases, the force of gravity will ________________
increase or get stronger
What is the name of the device that helps measure amount of force?
Spring scale
How will this object move?
3 N to the left
How do electrical forces push or pull objects?
Negative and positive charges attract or repel each other
What are the 2 properties that affect how strong the force of gravity is?
Mass and distance