Motion Notes

• Position-

location of an object after it moves. Known as the “distance” from the origin.

• Origin-the starting point of an object.

Most of the time it is (0,0) on a graph.

x=0

y=0

• Direction-

Movement towards or away from a particular position or reference point.

• Total Distance Covered-

sum of how far an object moves.

• Displacement-

how far from the origin an object ends or stops.

• Speed-

the amount of distance an object travels in a specific amount of time.

Formula v=d/t v= speed d=distance t=time

• Example of Speed-

An object travels 10 miles in an hours time. What is the object’s speed?

v=d/tv= speed=? (we need to solve for this)d= distance= 10 milest= time=1 hour

Plug in the values….v=10miles/1hr v=10mph

When an object moves at high speed more distance is covered in a short time. The graph would look like this:

Dis

tanc

e (k

m)

Time (sec)

When an object moves at slow speed it takes longer for the same amount of distance to be covered. The graph would look like this:

Dis

tanc

e (k

m)

Time (sec)

Practice

• Create a Distance/Time Graph for the following situation:

• You walk to the bathroom without a pass. You see Mrs. Wilson down the hall. You jump behind the lockers and hide for two minutes. When she passes, you turn and run back to the classroom so you won’t get caught.

• Acceleration can be a change in speed or direction.– An increase or decrease in speed is an acceleration.

– A motorcyclist who rides around the inside of a large barrel is constantly accelerating.

– A person riding a Ferris wheel at an amusement park is accelerating.

Acceleration is calculated by dividing the change in the object’s velocity/speed by the time over which the change occurs.

•

•

final velocity - initial velocityaverage acceleration

time

f iv v va

t t

• Inertia- tendency of an object to resist change in motion

• Example:

A pencil will sit on your desk indefinitely if it never experiences a change in forces.

A meteoroid will continue its motion in space unless it runs into something or gets pulled in by Earth’s gravity.

Frayer Diagrams

• Vocabulary:– Velocity– Acceleration– Inertia– Gravity– Mass– Weight

Term Definition

Picture/Symbol Example/Characteristics

Practice

• What determines how much an object speeds up or slows down?