NAME:____“Solutions”___

P221 Background Survey—(Spring 2007)

  1. What is your major?

Lots of Biologists, biochemists and chemists, with a sprinkling of other majors.

  1. Did you take a physics course in high school?

Only about a quarter of you have seen physics before, so don’t be worried if you haven’t, you’re not alone!!

  1. Have you previously taken M211 (or an equivalent calculus course)?

Only 5 of you are taking M211 concurrently, everyone else has completed calc I.

  1. What do you expect to lean from this course?

I expect to teach the basics of physics, and provide some useful practice at abstract thinking, the practical application of mathematics, and logical reasoning.

  1. What do you hope to do with the knowledge that you get from this class?
  1. What do you expect the lectures to provide?

The lectures should provide you with guidance on attacking problems, and some highlight some common problems students have. I will try to provide a different perspective on things than the book where appropriate. The primary purpose of the lecture will be (I hope) to clear up misconceptions and give clarifying examples and demonstrations. This will only work if we can get lots of class participation.

  1. What do you expect the text book to provide?

The text should be your primary source of basic information. Derivations and basic results should come from the text for the most part.

  1. What is the derivative with respect to time (t) of the following expressions?
  2. X(t) = 4.0 t3 + 0.5t2 + Xo

X’(t) = 12 t2 + t + 0 (assuming that Xo is a constant, which I forgot to specify, sorry).

  1. X(t) = 4.0 sin(t) + Xo

X’(t) = 4 cos(t) + 0 (most of you got a and b)

  1. X(t) = 4.0 sin(t3)+ Xo

X’(t) = 12 t2 cos(t3) + 0(most missed this, but this is well beyond what we will see in this course).

(85% of the class could do these, but only about half the class got them all correct; many of the mistakes were sloppy ones [0.25t in a for instance, or a minus sign in b or c] so it is clear that most of you are pretty familiar with derivatives)

  1. What is the integral (with respect to time, you may take A and Vo to be constants) of:
  2. V(t) = At + Vo

X= ½ At2 + Vot + Xo, where Xo is a constant

(about half remembered how to do this, but most of those forgot about the constant Xo)

  1. If no significant external forces act on an object over a certain period of time, what can you say about the motion of that object during that period of time?

The motion will remain unchanged.

(roughly ½ got this right)

  1. Find the length of the unspecified side of this triangle, and find the value of the angle identified as ? (if you don’t have a calculator, provide an algebraic expression to indicate how you would find each). tan() = 2/4 =>  =27 deg

X= sqrt(4+16) = 4.5 = 4/cos(26.6)

  1. Find the length of the unspecified sides of this triangle, and find the value of the angle identified as the value of the given angle is expressed in degrees)?
  2. Q = 180 – 90 – 65 = 25 deg
  3. Y = 2tan(65) = 4.29 = 4.3(=2/tan(25))
  4. X = 2/cos(65) = 4.73 = 4.7
  1. How many hours do you expect it will take for you to learn everything that you know from this course (include everything, lecture, labs, discussion sections, homework, self-study etc.).(expectations varied from 6 to 25 hours; 6 is unlikely to be enough (class, disc. lab is already 7, if you are spending 25, come to see me in office hours and we’ll see if we can reduce that time).