# Measuring and Graphing Motion

## 27 terms

### motion

an object is in________ when its distance from another object is changing

### reference point

a place or object used for comparison to determine if something is in motion

### changes

An object is un motion if it ________ position relative to an reference point

### International System of Units

abbreviation for SI

### 10

What number is the SI based on?

### Meter

What is the basic unit of lenghth for SI?

### 100

How many centimeters are there in a meter

### 1000

How many meters are there in a kilometer?

### Distance divided by Time

What is the formula used to calculate the speed of an object?

### Divide the total distance the cyclist traveled bt the total time

How would you find the average speed of a cyclist throughout an entire race.

### velocity

speed in a given direction is called

### the direction in which it is moving

an approaching storm is moving at 15km/hr. What do you need to know to determine its velocity?

### the horizontal, or x-axis

on a graph of motion, on which axis is the time shown?

### force

a push or pull on an object

### ways a unbalanced force can affect an objects motion

start it moving,stop the object,change the direction it is moving

### net force

the overall force acting on an object

### unbalanced force

net force changes an objects motion, the force is said to be

### contact force

when two objects are in contact, each exerts a force on the other that pushes it away

### friction

the force that one substance exerts on another when the two rub against each other, helps you walk and run

### gravitational force

pulls everything near Earth's surface toward Earth's center

### electrical forces

result from charged particles

### magnets

like poles of these repel

### acceleration

is the rate at which velocity changes, rewfers to increasing speed,decreasing speed, or changing direction,like a car following a gental curve in road,batter swings at abat to hit ball,a runner slows down after finishing a race

### speed and direction

acceleration involves a change in these things

### increased speed

makes an object expereince acceleration

### deceleration

another word for acceleration in which speed decreases

### the moon revovlving around earth

is acceleration because it is constantly changing directions