Objective

To calculate the average speed of an object
To calculate the average velocity of an object.

Equipment.

Blank paper
Calculator (a calculator is located on the widget page)
Pen or pencil

List of vectors for this homework.

a) 10 meters at 0 degrees.
b) 10 meters at 180 degrees.
c) 10 meters at 270 degrees.
d) 20 meters at 90 degrees.
e) 20 meter at 60 degrees.
f) -10 meters at 180 degrees.
g) 20 meters at 30 degrees
h) 15 meters at 300 degrees.

Assignment

For the following problems use the standard x,y coordinated system. Treat north as the positive y direction and east as the positive x direction. Image a car is driving around on the streets of physics town. Your job is to measure the average speed and velocity using measured distances and measured times.

Step 1

Calculate the distance and displacement between each step and calculate the total distance and displacement.
xy-graph.gif



Starting point

Step 1

Time to Reach Step 1

Step 2

Time to Reach Step 2

Step 3

Time to Reach Step 1
Origin
to
a
in
10 sec
then
b
in
30 sec




Origin
to
a
in
5 sec
then
d
in
20 sec




Origin
to
b
in
20 sec
then
d
in
10 sec




Origin
to
c
in
20 sec
then
f
in
5 sec
then
b
in
10 sec
Starting at b
then
g
in
10 sec
then
h
in
8 sec




Origin
to
g
in
8 sec
then
h
in
7 sec
then
a
in
5 sec
Origin
to
2 x a
in
5 sec
then
e
in
3 sec




Origin
to
c
in
20 sec
then
f
in
8 sec
then
d
in
3 sec



Step two

Calculate the speed an velocity the car is moving between each step.
Calculate the average speed and average velocity for the total trip in each problem.


Answer the following questions.
1. Ignoring the instants were the car changes it's motion were was the instantaneous velocity have the highest magnitude?
2. Ignoring the instants were the car changes it's motion were was the instantaneous speed the highest?
3. Ignoring the instants were the car changes it's motion were was the instantaneous velocity the highest? is question 1 and question 3 asking the same question? Can there be a different answer for 1 and 3? Explain.
4. Ignoring the instants were the car changes it's motion were was the instantaneous velocity the lowest?
5. Ignoring the instants were the car changes it's motion were was the average velocity have the highest magnitude? Where was the average speed the highest? Are the highest average velocity and the highest speed the same value? Explain why or why not.