Physics- Newton's Laws
Terms in this set (43)
What did Aristotle believe was the natural state of an object?
To be at rest
What did Galileo believe to be the natural state of an object?
He believed that an object would move forever until it reaches its initial height
What did Newton believe to be an objects natural state?
To be moving at a constant speed. He was correct
What is inertia?
The tendency of an object to resist a change in motion
What is Newton's first law?
A body will move at constant velocity unless acted on by an unbalanced force.
How is inertia measured?
Units of a Newton
when the net force on an object is zero
Equilibrium of an object not in motion
Equilibrium for an object in motion
A measure of the force of gravity on an object
What is Newton's second law?
What is Newton's third law?
For every action there is an equal and opposite reaction
What makes an action/reaction pair?
The forces have to be:
- equal and opposite
-acting on each other
Friction that acts on objects that are not moving relative to each other (ex- prevents an object from sliding down a hill) Fs
Friction between 2 surfaces moving against one another (box being dragged across floor). Aways opposes motion
Symbol for weight force
symbol for friction force
Symbol for Tension Force
Symbol for Applied Force
Symbol for Normal Force
the force perpendicular to a surface that prevents an object from falling through the surface
Rope or string force on an object
Resistance of the air (technically a fluid) against the forward movement of an airplane.
Gravitational Force equation and variables
F = Gm1m2/d^2
m2= mass 2
what is the constant G?
A force that opposes motion between two surfaces that are in contact
the net force acting on an object toward the center of the circle
centripetal force equation (also the friction force of the object in the circle)
Friction coefficient µ
ratio between friction force and normal force
µ= (two equations)
the motion of a falling object when the only force acting on it is gravity
any motion in which an object is moving along a curved path
Weightlessness in free-fall
An apparent absence of weight because a person is falling freely toward the Earth, hence there is no normal force (reaction force) acting on the person due to gravity
Why can't you feel the earth spinning?
the speed is constant, we can only feel acceleration
V average equation
2 equations for vf
inverse square relationship
intensity varies inversely with the distance from the source. Whatever factor by which the distance is increased, the intensity is decreased by a factor equal to the square of the distance change factor.
Why don't objects fall in circular motion?
The fall but they have sideways velocity
What does a net force of 0 mean
constant speed or motionless