Position
If its position changes relative to another object
Which is the best reason for not using a moving car as a reference point?
It is difficult to determine which direction motion is occurring.
To describe an object's motion, you need to know both its speed and its direction.
True
Which factor affects the strength of friction force?
The types of surfaces in contact
The force that pulls objects toward the center of the Earth is called:
Gravity
A person starts at one location, walks 15 meters east, then 10 meters west back to the starting point. What is the person’s displacement?
5 meters east
What is the formula for speed?
total distance divided by total time
What is Newton's First Law of Motion?
An object in motion will stay in motion unless acted upon by an external force.
A ball is rolling across the floor. Which force will most likely cause it to stop?
Friction
What is the measure of the amount of matter in an object?
Mass
What is the term for an object’s location relative to a reference point?
Position
What is velocity?
Speed in a given direction
According to Newton's Second Law, force equals
Mass times acceleration
What happens when balanced forces act on an object?
The object has no change in motion
How does mass differ from weight?
Mass is a constant, weight depends on gravity
What is the primary function of a reference point in describing motion?
To describe the position of an object relative to another object
What is acceleration?
The rate of change in velocity
What is Newton's Third Law of Motion?
Every action has an equal and opposite reaction
What happens to acceleration when net force increases (assuming mass stays constant)?
Acceleration increases
What is the relationship between mass and gravitational force?
As mass increases, gravitational force increases
On a distance-time graph, how can you show the speed of an object is increasing?
True or False: If a train is slowing down, it is accelerating.
True
What is inertia?
An object's resistance to changes in motion
If a person pushes against a wall and it does not move, the force they apply is balanced by. . .
Normal Force
What are the three noncontact forces?
Gravity, magnetism, electrostatic