# Homework Help: Average Speed/Average Velocity Problem

1. Sep 20, 2004

### pitchharmonics

I have a physics problem here that I need help solving. I need to figure out how to find the average speed and average velocity of a trip.

City A to City B is 55 miles with an angle 7.86 degrees west of north.

City B to City C is 75.5 miles with an angle 25.9 degrees west of north

City C to City D is 208 miles with an angle of 41.1 degrees west of north

City D to City E is 98.8 miles with an angle of 5.45 degrees north of west

----I take one 10 minute stop to fill up gas.

Then I return taking a scenic route:

City E to City F is 89 miles with an angle of 24.1 degrees east of south

City F to City G is 23.6 miles with an angle of 14.8 degrees east of south

City G to City H is 194 miles with an angle of 41.2 degrees south of east

City H to City A is 88.0 miles with an angle of 18.4 degrees south of east

--------I spend 45 minutes at each city on the way back

--------Average Speed for entire trip is 53.7 mi/h

1. what is the average speed and average velocity from City A to City C?

2. what is the average speed and average velocity from City C to City E?

3. What is the average speed and average velocity from City E to City A on the return?

Any help would be greatly appreciated!

2. Sep 20, 2004

### arildno

Any help might be given if you show some of your own work!

3. Sep 20, 2004

### pitchharmonics

Do I break this down into all the x and y components? of each vector?

Our book uses average speed and average velocty as if they were the same, what is the main difference

4. Sep 20, 2004

### arildno

Velocity is a vector quantity; speed is the (scalar) magnitude of that quantity.

5. Sep 20, 2004

### pitchharmonics

speed = total distance / total time

velocity = change in displacement/change in time

r cos angle= x component

r sin angle= y component

this is all I know