Wright State University Lake Campus/2016-9/Phy1110/log

29-Aug

Your account will span Wikiversity, Wikipedia, Commons, and Wikibooks.

1. No username can be anonymous on this campus. Your classmates will likely discover your identity. One option is to quasi-violate Wikimedia policy and have a "public" username, and different private one.
2. You are advised not to worry about previous consideration and pick a "permanent" username that you might use for the rest of your life. Pick an unembarassing username that not too long, avoid spaces and other odd symbols.

• You have three good choices for your password:

1. Use one you already know
2. Use one that you might forget, but give me the password. (Never give your "important" passwords to anybody; but keep in mind that very little harm is done if you give me your password
3. Use one that you might forget, but give them your email address. I am not certain, but it is my understanding that Wikimedia will retrieve your password if they have your email address.

5-Sep

Lecture: Vectors

Vector, vector addition, components, unit vectors

Transformations between (magnitude,direction) and (x,y components)

Lab: All present: Wikitext, permalinks Private wikifarm

• Private wiki at https://wikiversity.miraheze.org/wiki/Main_Page
• Importance of permalinks
• Set up student home pages for important links and image insertion

12-Sep 2d smith train and Malus law lab

• Two-d Smith train
• Review studyguide

• Lab choices:

Spitwad experiment

Malus law and vector components.

Next time
Run the lab 15 times and use the average.
Run in a channel to control the balls movement.
Have a slower acceleration. 


Present: '''Rimstock''', EmilyR, KTangeman26, NG18, Brackattack25, Crind

19-Sep velocity and acceleration

• Monday Lecture: Worked on Velocity and acceleration, focusing on questions pertaining to finding the acceleration. We did all but the first question ("When a table cloth is quickly pulled out from under dishes, they hardly move. This is because ..."),

26-Sep force table lab

Lab on force table: Reports on S-subpage to log. Rimstock

$x+\theta =180\deg$

$\tan \theta ={\frac {3}{4}}$

$\theta =\left(\operatorname {arctan} {\frac {3}{4}}\right)\cdot {\frac {180\deg }{\pi }}=X$

$180-X=\theta _{\text{actual}}$

$\theta _{\text{actual}}=180-\left(\operatorname {arctan} {\frac {3}{4}}\right)\cdot {\frac {180\deg }{\pi }}$

3-Oct Miraheze: Improve solution to static friction

• Most students have public wikis and know their passwords.
• Take attendance on Guy vandegrift
• Scanners in 196, 183,185, and library
• You have Skydrive through outlook. (Outlook related to email).
• https://wikiversity.miraheze.org/wiki/File:Physicsstaticfrictionproblem.jpg BrackAttack25CRind (discuss • contribs) 15:38, 5 October 2016 (UTC)

10-Oct Newton's III law

Can we "derive" Newton's 3^rd law?

1. Take attendance on Guy vandegrift for lab 12 October 2016 (UTC)
2. Guided derivation of Newton's third law. In the figure to the right, let is pretend we don't know how the string interacts with the two masses, but assume that a force

T₁ acts on m₁ and the force T₂ acts on m₂. Take both T₁ and T₂ to be positive quantities, but use your intuition to guide you as to whether the force is to the right (positive) or to the left (negative). Assume both masses are initially at rest and that the net force is to the left. Write down Newton's third law (F_e=ma) for 3 (three!) masses: m₁, m₂, and Σm =m₁ + m₂

24-Oct Centripetal force lab

Your report shall be handwritten on paper. We will cut and paste your efforts and try to produce a pdf file or a svg file to post on Wikiversity.

1. Sketch device in stationary mode, labeling rotating mass, m, hanging mass, M, radius of orbit, r. Write an equation involving the spring's force, F_S, the gravitational acceleration, g, any other variable that has been defined.
2. Set up the device and quickly measure m, M, r.
3. Derive a formula for F_S involving your measured values. This formula is essential and needs to be prominently displayed in the report. Also calculate this force in Newtons. Perhaps include an uncertainty in this value.
4. This is a "verification experiment", otherwise known simply as an experiment. We need two measurements of F_S that might or might not be equal to each other. Is there any other way to measure F_S ? Define v as the speed, and T as the orbit's period and write down two equations: One involves F_S and a=v²/r and the other involves v, r, and T. Your prof will write them on the board and discuss.

Footnotes

14-Nov Kepler's III, error averaging of times, 3 mass pendulum

link to commons

1. Proved kepler's III law and applied concept to g as function of r, T, m, M in whirly jig lab.
2. Verified that it seems to be better (?) to measure 10 cycles and divide by 10 to get period. Promise to continue w error propagation.
3. Watched part of the mit video and made our own 3 mass system and created video with Rimstock, KTangeman26, ng18, CRind, Emily_R, Brack_Attack25, and Guy vandegrift

See also this

28-Nov Fluid dynamics lab

Japanese Nuclear Piwer Plant "Mihama Reactor" had broken the 2nd cooling pipe in August, 9th. 2004. An orifice choked the water flow and the cavitation caved the usual steel pipe (not stainless steel). The low quality water and high temparture/high pressure accelerated the pipe wall thinning. Finally, the Hi-pressure and Flow-vibration had broken the pipe.

• Must add this explanation of Bernoulli "force" to wikiworld
• Wikipedia:Kelvin–Helmholtz instability -- Need to add this and this to wikiworld
• Tornado in a bottle youtube
• Fire tornado youtube]