danaleeling

I decided to combine the concept of using weights on a rope from a couple years ago with the pulling concept of last year to try to again find an equivalency between the acceleration generated by a force and the acceleration of the RipStik. I opted to use six kilograms which proved prescient, four would have been too little to overcome the massive friction with the beam above. I need a ladder, aluminum foil, and maybe light grease to make that rope run free. A clamp on pulley would be even better. Duck tape to keep the weights safely on the hangar is also a future need. I used the foam core radiant energy reflectors as cushioning. The basic layout can be seen above. I should have positioned the weight farther south, to the left, as I had to hold a post on the south side of the walk at start. This caused the rope to "walk" south as I rode forward, which put the weights to the south side of the pad. The distance over which I would accelerate is equal to the f...

This term I was battling a nice tropical head and chest cold. Devoid of energy and lacking much in the way of voice, I put directions on the board. I opted not to lead off with a demonstration - making this term different from prior terms. I did not run my usual "how does the penultimate marble know what to do" patter. I did have to adjust from groups of two to four to allow each group to have two stopwatches, a recorder, and a marble pitcher. Judy Andon and Mailynda Maycry Jasmine Santos and Mark Jones time marble runs Jessica Reyes and Lodonna Osawa discuss measurement approaches, Marti works with Laslyn in the background Data Data Set-up, donuts are optional Notes from the board plus data Group presentations focused on these two questions Mark Jones presenting Vanity Paul and Alex Etse jointly presenting Mailynda presents Jessica Reyes explains her group's findings  Marti Henry presenting Pernes B...

On Monday I tried to show that energy is conserved by trading GPE at the top of a slope for KE at the bottom. I used the covered walkway between the A and F buildings. My final velocity was difficult to obtain, I could only time the final 303 post-to-post centimeters to estimate my velocity. The real complication proved to be the height h. Without a level I could not accurately level the line I used to determine the height h. Memo to self: obtain a level before trying this again. Although I started in centimeters, the numbers generated by working in cgs (70000 g, 14140000 g cm/s of momentum) appeared to be clouding the physics for the students and worked against rounding to mentally comprehensible numbers. So I switched to MKS.  A mass of 70 kg (myself plus my RipStik measured using a metric spring scale), a g of 9.70 m/s², and a height of 0.09 meters yielded 62 Joules of GPE. A final speed of 3.03 meters/1.4 seconds (2.02 m/s) yielded a kinetic energy of 141 Joules. Thus my li...

Measuring the acceleration of gravity by timing the fall time for a super ball from 0, 100, 200, 300, 400, and 500 centimeters. This laboratory features a transformation of the x-axis. Squaring the time and then dividing by two and plotting against the fall distance yields a straight line with a slope equal to the acceleration of gravity. This brings a linear relationship into the heart of an acceleration measurement. This also reduces the complexity of the math down to where students with weak algebraic foundations can begin to understand the system mathematically. The lab in the text details the procedure. Marti Henry drops and times, Jessica Reyes holds meter sticks. V-ann retrieves the super ball Paulino Perman times and drops, Alex holds meter sticks, Mailynda Maycry records the data. Dropping from 400 centimeters is obtained outside. Lodonna Osawa and Jessica Reyes Marla Silbanuz records data gathered down the table Edward Reyes drops the supe...

The RipStik deceleration and acceleration built off of a lecture introduction first to negative slope, negative velocity, and a return to zero distance. I then suggested a gradually slowing, stopping and returning with acceleration would yield some form of curve. This built off of the last five questions on the velocity quiz last week. I finished the lecture demonstration with the arc of a ball on the board, parabolas, and the suggestion of a quadratic equation. Then I went outside to make one. I used the same zero post as the week before and a 305 cm on center measurement. After a couple practice runs I did a run that I thought went to 1220 cm out and back. I could not make the times work, became confused, and decided to redo the RipStik run. This time I realized I was turning just past the 915 cm post, so my original data was not faulty. The graphs below retain both sets of data. A roughly parabolic shape emerged from both runs, both runs have very similar time versus dist...

This term two students asked to meet the class at the trail head down by agriculture, and other were waiting down by the gym for the class. So at 3:20 PM I picked up moss with sporophytic spore capsules from the Premna obtusifolia on the eastern edge of the campus. I also grabbed a fertile Microsorum scolopendria frond and a Davallia solida frond. I knew a fertile kidou frond and ulungen kiehl would be harder to find on the trail. At 3:30 I was back at the classroom and headed west with the dozen students I found there. I found the cyanobacteria Nostoc at the east edge of the main parking lot along the drainage gutter. I put everything into a plastic bag. The one note for future terms is to bring more bags, smaller bags, clear bags. Everything was a jumbled mess by the time I reached the nan mahl. Heading west I took the most direct route, the students trailed in a broad arc. Up at the Lycopodiella cernua patch, which is increasingly well developed, I pulled out the Nostoc and be...

Since spring term 2014 laboratory two has been moved to occur between the LRC and the south faculty building. This laboratory builds on the Monday linear RipStik velocity homework which was then covered on Wednesday. The Wednesday lecture included the segment speed post-to-post for the RipStik to demonstrate that the speed is changing slightly and the slope, if inspected carefully, also reflects those subtle speed changes. Wednesday also saw coverage of stationary and infinite velocity objects on time versus distance graphs. This provides a solid introduction to laboratory two. The shift away from the gym was made to permit moving into the computer laboratory at the end of this laboratory to assist the students with making a graph with five trend lines and to continue to assist the students with using Schoology. This session is particularly necessary for getting laboratory one correctly submitted. Laboratory three will be the last laboratory in the term start set to use the computer la...