1. In the ratios below, give the value of the ratio, including units, then describe in complete sentences the meaning of each ratio.

a. (4 lbs of chocolate) / (5 people)

b. (-10 m/s + 4 m/s) / 3 s

2. a. Draw a reference frame, displacement vectors, and the total displacement vector for a dog that first walks 40 yds east, then 30° north of east for 60 more yards.

b. Suppose an object moves from position p1 = (2i + 3j ) m to p2 = (-5i + 7j )m in 5 seconds. Write down the average velocity vector (in unit vector form). 3. a. Below is the motion diagrams for two different objects C and D. Clock readings are indicated in the boxes.

3. a. Below is the motion diagrams for two different objects C and D. Clock readings are indicated in the boxes.

a) Which is travelling fastest to begin with?

b) Which travels the greatest distance ?

c) At which clock readings(instants) do they occupy the same location at the same time?

d) Is there any time interval over which they have the same average velocity?

e) Are they ever travelling the same speed at any clock reading? If so, when?

f) Which would accurately indicate the speed of the object at clock reading 2, an arrow drawn from 2 to 3 for C or an arrow drawn from 2 to 3 for D?

3. b. Draw a motion diagram on the reference frame below for a car moving with positive acceleration and negative velocity.

4. a. Use complete sentences to describe the motion of the object with the velocity vs time curve below:

4b. Find the total displacement traveled in 7 seconds by the object with this velocity vs time curve.

4c. Draw the acceleration vs time and displacement vs time (assume the object starts at the origin ) graphs for the object with the following velocity vs time graph.

For the first problem below, here's how you get paid:

Draw picture -1 point

Draw reference frame -1 point

Draw motion diagrams for each object over each time interval (if different) to determine signs for velocities and accelerations. -1 point

Indicate with A, B, C, etc, the pertinent events. -1 point

Write down x, v, and t values for each object at each of these positions, and acceleration between them. -1 point

Solve the problem -1 point

5a. A metro train in Washington, D.C., starts from rest and accelerates at 2.0 m/s2 for 12 s. The train travels at a constant speed for 65 s. The speed of the train then decreases for 24 s until it comes to a stop. What is the total distance between stops?

5b.. Martha is riding in a hot air balloon, rising at a constant 5 m/s. George watches nervously from the ground. At 30 m according to her altimeter, she releases Harry, George's teddy bear, for George to catch. Assuming you can ignore air resistance and the acceleration due to gravity is 10 m/s2, how fast is Harry travelling when he reaches George?
6. a. Given the two vectors below, draw the vector: Use two separate diagrams.

a) A + B and Label it!
b) A - B and Label it!

6b. Given A_y = -3 m and = 210^o, draw A , find A_x and A.

7. The Hovercraft is initially moving in the x direction for about 10 feet, then at the bean bag someone suddenly begins to apply a constant force F = 5 lbs parallel to the y axis.

a. Draw the y vs x motion diagram for this motion on the diagram above (that is, draw the path the Hovercraft takes).

b. Also on the diagram above, draw the motion diagram for the object in both the x and y directions.

c. Draw the vx vs t and vy vs t curves on the diagrams below.

8. The graph below shows the position vs. clock readings of the motion of two trains running on parallel tracks.

Which of the following is true:

A. at time tB both trains have the same velocity

B. both trains speed up all the time

C. both trains have the same velocity at some
time before tB

D. somewhere on the graph, both trains have
the same acceleration

10 point BONUS QUESTION: As the ball rolls down this hill:
WOW! You Crazy Man? This Is Easy!

1. its speed increases and acceleration decreases

2. its speed decreases and acceleration increases

3. both increase

4. both remain constant

5. both decrease