PHYS
Physics Lab write up 10

# For the analysis part of the experiment the student

• Notes
• 3
• 100% (1) 1 out of 1 people found this document helpful

This preview shows pages 2–3. Sign up to view the full content.

For the analysis part of the experiment the student will use the values for the maximum angular velocity (ω max ) of the smart pulley, calculate the angular velocity (ω) of the rotating disk, using the formula, ω D max (R P /R). Then record the values in table I. Next by using the calculated values for the angular velocity (ω) of the disk and the dimensions of the disk and spool, calculate the speed of the outer edge of the disk. Also, calculate the speed of the falling mass. Record this data in table I. Next the student will find the formula for the moment of inertia of a disk, by using the necessary measurements of the disk, calculate the moment of inertia of the disk (I). Then record the data in table I. For each trial, the student will calculate the change in gravitational potential energy of the falling mass, ΔP.E.= -mg(H 1 -H 0 ) then record the data in table II. For each trial, the student will then calculate the change in rotational kinetic energy (Iω D 2 /2) of the rotating disk. One could also use the velocity of the outer edge of the disk (V D ) to determine the kinetic energy (MV D 2 /4). Record the results in Data table II. Part of the gravitational potential energy also goes into the kinetic energy mv 2 /2) of the falling mass. Calculate the translational kinetic energy of the falling mass for each trial. Record the data in table II. Next determine the total change in kinetic energy (ΔK.E.) by adding the rotational energy of the disk to the translational energy of the falling mass. Record this data in table II. Next find the total change in energy and record the values in data table II. Last the student will determine the percent difference between the changes in the potential and kinetic energies; record the results in data table II. In our experiment the percent differences were over a hundred (130%-150%), which could be, because we did not account for friction or the energy lost to sound and heat but our percent differences increases slowly as the weight of the falling mass increases. Unfamiliar Terms : Conservation of energy principle : states the total change in the kinetic energy (ΔK.E.) should be equal in magnitude and opposite sign to the total change in potential energy (ΔP.E.). (from the lab manual) Kinetic Energy : the mechanical energy that a body has by virtue of its motion ( wordnetweb.princeton.edu/perl/webwn ) Potential Energy : the mechanical energy that a body has by virtue of its position; stored energy ( wordnetweb.princeton.edu/perl/webwn ) Inertia: the tendency of a body to maintain its state of rest or uniform motion unless acted upon by an external force ( wordnetweb.princeton.edu/perl/webwn ) Translational kinetic energy

This preview has intentionally blurred sections. Sign up to view the full version.

This is the end of the preview. Sign up to access the rest of the document.
• Fall '11
• BrunoBauer

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern