Force
Any push or pull which causes something to move or change its speed or direction
Forces can be...
Balanced or unbalanced
Balanced forces are ...
equal in size and opposite in direction
Unbalanced force are...
unequal in size and/or opposite in direction
If the forces on an object are unbalanced, a _________ results
net force
Newton's First Law of Motion
An object at rest stays at rest and an object in motion stays in motion at the same speed and in the same direction unless acted upon by an unbalanced force
Newton's 1st law is also called...
the law of inertia
Inertia
Objects tend to resist change in motion
The greater the mass, the greater/lesser the inertia
greater
The greater the speed the greater/lesser the inertia
greater
Friction is...
an unbalanced force that opposes or slows down motion
Four main types of friction
Sliding, rolling, fluid (air or water resistance) static (initial friction when moving an object)
Friction is caused by...
the physical contact between moving surfaces
The amount of frictions depends on...
The type of surfaces and the force pressing the surfaces together
Friction changes motion into...
heat
Newton's 2nd Law of Motion
The net force of an object is equal to the product of its mass and acceleration (AKA F = ma)
One newton is equal to...
One newton is equal to...
Newton's 3rd Law of Motion
For every action, there is an equal and opposite reaction
Gravity
An attraction force between all masses
Rate of gravity on earth
9.8 m/s�
Newton's Universal law of gravitation
every object in the universe exerts a gravitational attraction to all other objects in the universe
The amount of gravitational force depends on...
the mass of the objects and the distances between the objects
Gravity - the greater the mass, the greater/lesser the force
greater
Gravity - The greater the distance, the greater/lesser the force
lesser
Weight is measure of...
gravitational force between two objects
The greater the mass the greater/lesser the force(weight)
greater
Weightlessness
Free from the effects of gravity
Regardless of mass, all objects fall with the same acceleration due to _____
inertia
Weight
Gravitational force exerted on an object
Weight decreases as....
an object moves away from earth
Mass is a measure of...
how much matter an object contains
Weight results from ____
force
Centripetal acceleration is the acceleration of an object...
toward the center of a curve or circular object
Air resistance
The force of air exterted on a falling object
What is reached when air resistance = force of gravity?
Terminal velocity
Projectiles follow a _____ path
curved
The two forces that affect projectiles
Horizontal velocity (inertia) and vertical velocity (gravity)
centripetal means...
to move towards the center
Terminal velocity
the highest velocity an object will reach as it falls
Air resistance opposes...
gravity
The amount of air resistance depends on an object's _______, _______, and _______.
shape, size, and speed
Terminal velocity - forces are balanced/unbalanced and object falls with constant/changing speed
balanced, constant
equation for momentum
p = m*v where p = momentum, m = mass, v = velocity
law of conservation of momentum
when objects collide the momentum of one object is transferred to the other object
Distance
how far an object has moved
displacement
how far an object has moved in relation to its starting point.
frame of reference
the object or point from which movement is determined
speed
the distance traveled in a given amount of time
calculating speed
distance/time or d/t
constant speed
speed does not change over time
average speed
speed of motion when speed is changing
calculating average speed
total distance/total time
instantaneous speed
speed at any given moment in time
velocity
speed + direction
acceleration is
a measure of change in velocity
positive acceleration
speeding up
negative acceleration
slowing down
calculationing acceleration
kmkk