The mass of most objects are too small to cause a force large enough to move objects toward each other.
100
Why does friction occur?
Because the surface of any object is rough, and when they come in contact, friction occurs
100
What is net force?
It is the combination of all the forces acting on an object.
200
The rate at which velocity changes over time; an object accelerates if its speed, direction or both change
acceleration
200
Final velocity minus starting velocity divided by the time it takes to change velocity
average acceleration
200
What was Sir Isaac Newton's law about gravity called?
The law of universal gravitation
200
Which has more friction and why? Smooth surfaces or rough surfaces?
Rough surfaces because they have more microscopic hills and valleys.
200
When two forces are exerted on an object in the same direction, are the forces added or subtracted to determine the net force?
They are added.
300
A force that opposes motion between two surfaces that are in contact
friction
300
What is the most common unit of speed?
meters per second
300
What is part 2 of the law of gravitation?
Gravitational force decreases as distance increases.
300
Name the two types of friction.
Kinetic and static.
300
If 10 newtons of force is exerted on an object on the left and right side and 10 newtons of force is exerted on the bottom, which way will the object move?
The object will move upwards.
400
A force of attraction between objects that is due to their masses
gravity
400
What is the unit of acceleration?
(m/s)/s or m/s(squared)
400
why are weight and mass often confused?
weight and mass are often confused because they are constant on Earth
400
When does static friction occur?
When a force is applied to an object but does not cause the object to move.
400
When is a force balanced?
When the forces on an object produce a net force of zero newtons.
500
A push or pull exerted on an object in order to change the motion of the object; has size and direction
force
500
What is the unit of force?
newtons
500
What is part 1 of the law of universal gravitation?
Gravitational force increases as mass increases.
500
When does rolling kinetic friction occur?
When anything that has wheels is involved.
500
What kind of force is necessary to cause a non-moving object to start moving?