How Far?_________ (d)

____________________________________________________________________________

To get to the store go 2-miles east, turn right and go 3-miles south.

How far will you travel to the store?__________________

Notes on Motion III

How Fast. How Far & How Long

How Far?Units for distance are:

English System

_____________, ______________, ______________

Metric System

_____________, ______________, ______________

In science the most common unit is:

_______________

How Fast?Speed (v)

__________________________________________________________________________________________

Velocity (v)____________________________________________________________________________________________

If you are traveling north at 65-mph.Your speed is : _________

Your direction is : ____________Your velocity is : ____________

How Fast?Average Speed (vavg)

____________________________________________

_____________________________________________

Average Speed is over a _______________.

Instantaneous Speed (v)

___________________________________________

___________________________________________

Your speedometer measures ____________________.

How Fast?Constant Speed (v)

_______________________________________

Constant Velocity (v)_______________________________________________________

Can you have a constant velocity but not have a constant speed?

Can you have a constant speed but not have a constant velocity?

How Fast?Units for speed and velocity:

English System__________________, __________________

Metric System________________________________________,

_______________________________________

In science the most common unit is:

How Long?_______ (t)

Units:

__________, __________, __________, __________,__________

In science the most common unit is:

Solving Problems with Velocity and Speed

In general the equation that relates the speed (or velocity) of an object to the distance it

travels and the time it takes is:

If we need to find the distance from speed and time, we use algebra to solve for d:

If we need to find the time from distance and speed we use algebra to solve for t:

Solving Problems with Velocity and Speed

We can use a triangle to help us remember these formulas.

Solving Problems with Velocity and Speed

dv t

Example Problem 1:

A runner finishes the 100-m dash in 9.4-s. What is the average speed of the runner during the race?

Know: Find:

Formula: Solve:

Solving Problems with Velocity and Speed

dv t

Example Problem 2:

A car travels with a constant velocity north of 45-m/s (100-mph). How far will the car travel in 300-s (5 minutes)?

Know: Find:

Formula: Solve:

Solving Problems with Velocity and Speed

dv t

Example Problem 3:

The circumference of the Earth is approximately 40,000-km. How long would it take you to drive this distance at 320-km/hr?

Know: Find:

Formula: Solve: