What is net force?
All the forces acting on an object
If the forces acting on an object are going in the same direction, you would _________ them together to get the net force.
ADD
If the forces are acting on an object are going in opposite direction to each other, you would _________ them together to get the net force.
Subtract
What is inertia?
The tendency of an object to resist a change in its motion
The greater the mass of an object will ______ its inertia.
increase
What is weight?
The force of gravity on a person or object on the surface of a planet
How can we increase acceleration of an object?
Decrease its mass Increase force
What is friction?
The force that one surface exerts on another when the two rub together
What is rolling friction?
Occurs when an object rolls over another object Example: bike tire on a road
What is free fall?
Occurs when the only force acting on a falling object is gravity
Air resistance is a form of __________
Friction
The Law of Universal Gravitation states ____________________
Any two objects in the universe are attracted to each other
What is the formula for momentum
Mass x velocity
What is force?
A push or pull on an object
How can you increase momentum?
Increase the velocity (speed) of the object Increase the mass of the object
What is mass?
The amount of material (matter) in an object
How can you increase friction?
Make the surfaces rougher Example: sand on an icy sidewalk
What is gravity?
The force that pulls objects toward earth
What is Newton’s third law and give an example.
For every action there is an equal and opposite reaction Example: a hammer hits a nail and the nail exerts a force back on the hammer
If forces on an object are balanced,
The object will never change its motion (move)
If the forces on an object are unbalanced,
There will be a change in the objects motion
What is the formula that describes Newton’s 2nd law of motion?
Acceleration = net force x mass
What are two factors that affect gravitational pull?
Mass of the objects The distance between the objects
On the arrow below, what does the point of the arrow indicate?
The direction of the force
On the arrow below, what does the length of the arrow indicate?
The strength of the force
In what direction is the net force acting?
To the left
From what direction must force be applied so that forces are balanced?
To the left
If a third force is applied to the object, in what direction will the object move?
Up and to the left