1,166=x
11.66=y
67=z
1. Write down an explanation, based on a scientific theory, of why objects fall if they are held up
above the ground and then let go. Explain why it is scientific. Then write down a non-scientific
explanation of the same phenomenon, and explain why it is non-scientific. Then write down a
pseudoscientific explanation of the same phenomenon, and explain why it is pseduoscientific.
2. You need to lift a person with a mass of Z kilograms who is laying in bed into a wheelchair
next to the bed. If the distance from your hand to your elbow is Y centimeters and the distance
between your shoulder and lower back is Z centimeters, how much force will your lower back
muscles experience if you lift by leaning over the wheelchair? Sketch a diagram to help explain
your reasoning, and show your calculations.
3. Referring to Question 2 above, how much force will your lower back muscles experience if
you lift by sliding the person in a seated position into the wheelchair while you maintain as
upright a position as possible? Refer to the diagram from Question 2 above or draw a new one.
4. For each of (a) and (b) below, write a single grammatically correct sentence containing the
words indicated that makes scientific sense. You may use conjunctions; a list of definitions,
however, will not receive credit.
(a)
5. Write a question appropriate for this exam that requires a mathematical calculation about the
rotational displacement of an object with an angular acceleration of Y radians per second
squared and initial angular velocity of Z radians per second. Then answer it. You will be graded
on both the appropriateness of the question and the correctness of the answer.
6. (a) How much potential energy would be added to an object of mass X kilograms lifted Z
meters into the air? (b) If that object were dropped from that height, how far off the ground would
it be moving at Y meters per second? Or would it not get that fast before it hit the ground?
Remember to show your calculations and reasoning.
7. Write a question appropriate for this exam that computes the parallel and normal forces
exerted on an object of Y kilograms sliding down a 30-degree inclined plane with a coefficient of
friction of 0.3. Draw a sketch of the system in the question, labeling the key quantities. Then
answer the question. You will be graded on both the question’s appropriateness and the
answer’s correctness.
8. Three children are playing on a skating rink. Allie slides eastward and runs into Billie and
imparts a force of Z newtons. Callie slides northward also runs into Billie and imparts a force of
Y newtons. Billie’s mass is Y kilograms. Draw a diagram of this system, labeling any vectors or
quantities that are significant; then calculate Billie’s velocity one second after the collisions.
9. Write a 20-40 word paragraph answer to this question: based on your understanding of
rotational motion, do you think would it be better for your shoulder joint to do windmill exercises
with your arms rapidly or slowly? Explain your answer, citing any references you use.