Chapter 15- Forces and Motion Flashcards
What are forces measured in?
Forces are measured in units called newtons
What is a force?
A force is a push or a pull
What is friction?
Friction is the force that resists the movement of one surface past another
What are two examples of moving friction?
Rolling friction and sliding friction
What is gravitational force?
The force of attraction between any object and every other object in the universe
Who was the first to explain many details about gravity?
Isaac Newton
The gravitational force of the _____ lowers the tide and exposes the land.
Moon
What is a tide?
A rise or fall of the water level near the ocean shore
What are used to describe motion?
Speed, velocity, and acceleration
What is speed?
A measure of how fast an object is moving
What is velocity?
The speed of an object in a particular direction
What is acceleration?
The rate at which velocity changes
What is needed to change an objects motion?
A force
What is Newton’s first law of motion?
An object at rest remains at rest while an object in motion remains in motion at a constant speed in a straight line, unless acted on by an unbalanced force.
What is inertia?
The tendency of an object to remain at rest or in constant motion unless a force acts on it.
What is Newton’s second law of motion?
The acceleration of an object depends on the mass of the object and the size of the net force applied.
How is the second law of motion written as an equation?
Acceleration= force/mass
What is Newton’s third law of motion?
When a force is applied to an object the object exerts an equal force in the opposite direction.
What is Newton’s third law of motion sometimes called?
The law of action and reaction
What is momentum?
Is it can be used to find the force needed to stop a moving object
Which type of friction acts on a box that is moving down a ramp?
Sliding
What is a force that keeps planets orbit?
Gravity
What can be used to figure out the force needed to stop a moving object?
Momentum
What is the unit of force?
Newton (n)
