position

the location of a place or object

reference point

a location to which you compare other locations

motion

the change in position over time

observation of movement

depends on the position and motion of the person doing the observing

speed

a measure of how far something moves (or the distance it moves) in a given amount of time

velocity

speed in a specific direction

vector

a quantity that has both size and direction

acceleration

rate of change in velocity

What are two ways to describe the location of a specific city?

 longitude and latitude

&

the distance from a specific reference point

If it is 30 miles from Hartford to Simsbury, why might a driver have to travel 42 miles to get from one place to another?

30 miles is the straight-line distance from Hartford to Simsbury. However, there are no routes from Hartford to Simsbury that are a straight line. There are multiple routes that have many curves, which increases the travel distance.

How can you tell if motion has occured?

There has been a change in position.

Formula for speed

S = d/t

S = speed

d = distance

t = time

Why is velocity an example of a vector while speed is not.

A vector is a quantity that has both size and direction. Speed is not a vector because speed is a measure of how fast or slow an object moves, not the direction it moves in. Velocity has a size (speed) and a direction, so it is a vector.

When is the only time acceleration can occur?

Acceleration can only occur when velocity changes.

If velocity is not changing, then there is no acceleration.

the formula for acceleration

 acceleration = (final velocity - initial velocity)/time

a = (v_f - v_i)/t

 difference between instantaneous speed and average speed

Instananeous speed is the speed a one specific moment and is difficult to measure. Average speed is a measure of how quickly one moves over a distance, is easier to calculate, and is a more accurate measure.

basic unit used to measure speed

meters per second

m/s

difference between speed and velocity

velocity has direction, and speed does not

positive acceleration

when velocity increases (when things move faster)

constant velocity

when velocity does not change (when something moves at same speed and in the same direction)

negative acceleration

when velocity decreases (when something slows down)