Level 52 Level 54
Level 53

## Ignore words

Check the boxes below to ignore/unignore words, then click save at the bottom. Ignored words will never appear in any learning session.

Ignore?
inertia
_______ is the property of an object that leads it to resist any change in motion
Magnitude...
... of a vector is always a positive quantity
net force
Acceleration depends on the
balanced forces
forces that are equal in size but opposite in direction
unbalanced forces
forces that cause a change in the motion of an object
friction
a contact force; type of force between two touching surfaces
gravity
(physics) the force of attraction between all masses in the universe
Newton
(kg*m)/(s*s)
balanced force
Equal forces acting on an object in opposite directions
Kinetic Friction
Friction between moving surfaces
static friction
A car drives with its tires rolling freely. Is the friction between the tires and the road kinetic or static?
Sir Isaac Newton
Gave us the 3 laws of motion
1st Law
An object at rest stays at rest, an object in motion stays in motion, UNLESS an UNBALANCED force acts upon it.
2nd Law
Acceleration is produced when a force acts on a mass
3rd Law
Every action has and opposite re-action
greater friction
Rougher surfaces have
False
(T/F) Tycho Brahe was a Danish astronomer who confirmed Copernicus's theories by making many observations with his telescope.
gases and liquids
Fluid friction can involve_______ and _______.
Give an example of fluid friction.
An arrow flying through the air.
type of surface or texture
The size or magnitude of friction between two objects depends on _______.
how hard surfaces push together
The size or magnitude of friction between two objects also depends on _______.
unbalanced or unequal
In order to make something move, the forces on it must be_______.
rolling
A train demonstrates _______ friction.
balanced
adj. in a state in which equal and opposite forces cancel each other out
sliding
A sled is an example of _______ friction.
motion
An object is moving if its position relative to a fixed point is changing.
not moving
Balanced forces act on objects that are
Reference Point
A _______ is a place or object used for comparison to determine if something is in motion.
Speed
Units: cm/s, m/s, mi/hr, km/s ...
Velocity, speed, direction
_______ is an objects _______ in a specific _______.
acceleration
(physics) a rate of change of velocity
Velocity
a speed in a particular direction.
Unbalanced
Unequal forces acting on an object is a _______ force.
free fall
a state in which an object is gravitationally drawn to the earth's surface and is unaffected by any forces besides weight
Air Resistence
Objects falling through the air experience a fluid friction called _______.
Terminal Velocity
Greatest velocity an object can reach is called _______.
Meter
base unit of length in the metric system. Approximately 39.37in.
seconds
A car traveling at 7.0 m/s accelerates uniformly at 2.5 m/s^2 to reach a speed of 12.0 m/s. How long does it take this acceleration to occur? (units)
mass
a body of coherent matter, usually of indefinite shape and often of considerable size
weight
A force that comes from gravity pulling down on any object with mass
slope
On a X vs. t graph, the velocity is represented by the_
Linear
Bond Angle - 180°
Non-linear
A graph that does not have a straight line is _______.
momentum
(p) vector quantity describing the quantity of motion or inertia in motion. Recognizes that both mass and velocity have a part in the motion of an object and is proportional to both (is zero …
The Law of Conservation of Momentum
The total momentum of the objects that interact does not change', this law is called _______ __ _______ __ _______.
work
a force acting upon an object to cause a displacement. (key words: force, displacement, and cause)
Joule
Unit for work is?
Machine
A device that makes doing work easier.
Input Force
The force "you" exert on the machine is called _______.
Output Force
The force exerted by the machine is called _______.
Efficiency
_______ compares the amount of output work to the input work.