physical science chapter 11 motion keyterms

An object’s change in position relative to a

reference point is known as

Motion

A _________ of ___________________

is a system for specifying the precise

location of objects in space and time

frame of reference

_______________ measures the path an

object takes (how far an object moves

along its path). You need to know the

distance to correctly describe the objects

motion.

Distance

A change in position of an object is known

as ____________________

Displacement

Measures how far between the __________

point and ______________ point

____________ of displacement must be given

(toward or away)

starting,ending,direction

How fast an object moves is known as

____________

Distance

Speed = distance/time

Speed

The ____________ of an object is the

speed and direction of the object’s motion.

It is described relative to a _______________

point

Either positive or negative

Combined velocities determine ___________

velocity

velocity,reference,resultant

To calculate speed, you must measure the

____________ traveled and the

_________ it took to travel that distance

distance,time

Average speed is calculated as

distance

divided by time

The unit for speed is ____

M/S

When an object covers equal distance in

equal amounts of time, we say it has

________________ speed

constant

The speed measured in an infinitely small

time interval is known as

____________________ speed

instantaneous

The ____________ the time interval, the more

_______________ the measurement of speed

smaller,acurate

We graph motion by distance vs. time

The slope equals ____________

speed

The rate at which velocity changes over

time is _____________________

acceleration

Acceleration can be a change in

____________ and/or ________________

speed,direction

____________________ acceleration is

acceleration that occurs in a circular

motion

Centripetal

Calculating ________________________:

acceleration

Positive acceleration = _____________ ____

speed, up

Negative acceleration = _________ _______

slow down

Graph acceleration by ____________ vs._______

speed,time

Slope is equal to _______________________

accerleration

________________ acceleration is when the

speed changes by the same amount over

each time interval

constant

Any ___________ that can change the

state of motion of an object is called a

_______________

action,force

The four fundamental forces are:

_______________

___________________________ force

Strong ______________ force

Weak _______________ force

gravity,electromagnetic,nuclear,nuclear

Fundamental forces vary in ___________

nuclear

Strong nuclear force is the strongest, but only

at distances the size of an atomic _________

nucleus

Pushes or pulls are called _____________

forces because they require objects to be

touching each other for the force to occur

contact

___________ forces, on the other hand,

do not require objects to touch each other

field

The combination of all

of the forces acting on

an object is called the

_____ ___________

net force

Net force determines if

the object will change

its ______________

The object will

__________________

in the direction of the

net force

motion,acceleration

________________ forces do not change

the motion of an object

balanced

______________________ forces

do not cancel completely, so there is motion!

Object will move according to the ______

force

unbalanced, net

Forces can affect motion in several ways:

They can make objects __________ moving

They can make objects move ____________

They can make objects move ____________

They can make objects ________ moving

They can make objects change ___________

They can make objects change ___________

#

start

faster

slower

stop

directions

shape

Since force cause changes in the speed

or direction of an object, we can say that

forces cause changes in _____________,

so…forces cause ___________________!

velocity acceleration

Forces are measured in ______________ (N)

Forces usually act in _________

Forces act in a particular ________________

Forces usually cannot be __________, but

their effects can

newtons

pairs

direction

seen

The unbalanced force that acts against an

objects direction of motion is called

_______________.

friction

Always __________________ the motion

Surface is ____________; rubbing of the two

surfaces creates _________.

opposes

rough

heat

_____________ friction is between

surfaces that are stationary

static

Friction between moving objects is

_______________ friction

kinetic

Static friction is usually ___________ than

kinetic friction

greater

Types of kinetic friction:

______________ friction: when objects slide

past each other

______________ friction: rounded object that

rolls over a smooth surface

sliding

rolling

Unwanted friction can be _____________

using:

lowerd

Helpful friction can be _______________

By making surfaces ______________

Greater friction if the force pushing surfaces

together is ___________________

(more mass = more friction)

increased

rougher

increased