Week 2 (Aug. 18, 20, 21, 22)

Reading: PSE Chap 1, Physics and Measurement
Topics: Units and dimensional analysis, significant figures, keeping a laboratory notebook.

Quiz on Monday

Week 2 Exercises:

  1. Pendulum laboratory
    • Study the guidelines for how to keep a laboratory notebook.
    • Suspend a pendulum bob from a thin cord. Pull it back, release it, and measure the time for one oscillation. How far did you pull it back? How long was the pendulum? What is the weight of the bob? Be sure to estimate and record the uncertainty in each of your measured quantities.
    • Repeat this procedure for several different cord lengths, recording your procedure and data in your lab book notebook
    • Using Logger Pro, make a (beautiful) plot of the period of oscillation (on the y-axis) as a function of the pendulum length (on the x-axis). Be sure to clearly label your axes and make your data points large and visible (but not too large).
    • Does your data behave as you expect, based on dimensional analysis? Fit an appropriate mathematical function to your data to see if it matches your expectations.
    • Print your plot and fix it securely into your laboratory notebook. Explain what you learned from your experiment and what you would do differently if you were to do the experiment again.
    • Scan and submit all of the laboratory notebook pages from our pendulum experiment this week.
  2. Coulomb's law dimensions: Coulomb's law allows one to calculate the force that one electrical charge exerts on a second, nearby, electrical charge. The formula for Coulomb's law is: (Force) = (coulomb's constant) * (charge 1) * (charge 2) / (distance between charges)^2. Don't worry if you are not familiar with this formula. Just use the technique of dimensional analysis, to determine the dimension of coulomb's constant. What might be the units of coulomb's constant? Hint: the dimension of charge is Q and the MKS units are Coulombs.
  3. Density and significant figures: Calculate the density (in grams per cubic centimeter) of a solid cube that measures 5.00 cm on each side and has a mass of 351 grams. Pay careful attention to significant figures. How many are there in your answer?

Registration for College Credit: Wisconsin Lutheran College is requiring students in this course who are interested in obtaining college credit. Please apply in the application link below for each class you are wishing to apply for college credit. This must be approved by Friday, September 27.

https://admissions.wlc.edu/register/foundations

Once students apply we will wait for Wisconsin Lutheran College to confirm eligibility and requirements for college credit and communicate out further information. Please reach out to Mr. Davis if you have any questions.

Classroom problems: As a reminder, these are some of the problems we worked out in class…
  1. Dimensional analysis: determine how the period of a pendulum depends on its length and the acceleration of gravity.

General College Physics