# Measuring Motion

### Different types of motion in physics

## Speed

- Definition: Distance traveled by an object divided by the time taken to travel that distance.

- Measured in meters per second(m/s)

- Formula for speed: S=d/t
- Since objects don't usually travel at a constant speed you typically just give average speed.

## Velocity

- Definition: speed of an object in a specific direction.

- The formula for velocity is v=d/t.
- An object's velocity is constant if the direction or speed doesn't change.
- The velocity will change if the direction or speed changes.
- There is also
**resultant velocity**- the combined velocity of different objects in motion.

- Speed and velocity are NOT the same.

## Acceleration

- Definition: A measure of how much the velocity changes in a certain amount of time.

- An object accelerates if its direction,speed, or both change.
- There is
**positive acceleration **(increase in velocity) and **negative** **acceleration (**decrease in in velocity.) - The faster the change in velocity is, the great acceleration there is.

## Work

- Definition: When a force causes an object to move in the direction that force is applied over a distance(or force) that stops the movement.
- The formulas for work is W=Fd.
- Work is measured in joules(J).
- If there is no movement over a distance the is no work.
- There is
**positive work**- when motion and force are in the same direction and **negative work- **when motion and force are in opposite directions.