Energy
the ability to do work
Potential energy
stored energy that is available to use later
Kinetic energy
the energy of moving objects (energy of motion)
Work
is done when a force is used to move an object
Joule
SI unit of work or energy
Motion
an object's change in position relative to a reference point
Reference point
A place or object used for comparison to determine if an object is in motion
Speed
rate at which an object moves
Velocity
the speed of an object in a particular direction
Acceleration
rate at which the velocity changes (when an object speeds up, slows down, and/or changes direction)
Force
a push or a pull that acts (exerted) on an object
Balanced forces
set of forces acting on an object that cancel one another (equal and opposite) so that there is no movement of the object; net force=zero
Unbalanced force
a set of forces acting on an object that do not cancel out changing the motion of an object
Net force
total amount of force being applied to an object, also called the resultant force
Gravity
a force that pulls objects toward each other, a force that attracts objects to each other
Friction
a force that opposes motion between objects that are touching
Applied force
involve direct contact with an object (a push or a pull)
Tension
the state of being stretched tight; apply a force to (something) that tends to stretch it
Inertia
the tendency of an object to resist a change in motion
Newton's First Law
law of inertia - an object will not move or change its motion unless it is acted upon by an unbalanced force
Newton's Second Law
law of force and acceleration - the acceleration of an object depends on the mass of the object and the net force applied (F=ma)
Newton's Third Law
Law of action/reaction - whenever one object applies a force on a second object, the second object applies an equal and opposite force on the first object
Newton
the SI unit measurement for force
Mass
a measure of the amount of matter in an object
Exert
to apply a force onto an object
Constant speed
when the speed of an object remains steady/doesn't change
Calculate
determining something mathematically
Air resistance
the friction experienced by an object moving through the air
When is an object in motion?
When its distance from a reference point changes
What causes an object to accelerate?
an unbalanced force