https://physlab-wiki.com/ 2026-04-14T12:57:03+00:00 https://physlab-wiki.com/ https://physlab-wiki.com/lib/tpl/UChicago/images/favicon.ico text/html 2024-06-11T16:34:45+00:00 Anonymous (anonymous@undisclosed.example.com) https://physlab-wiki.com/phylabs/lab_courses/phys-211-wiki-home/drop-pinch-off/camera-notes?rev=1718138085&do=diff High-speed camera notes The TA and laboratory staff will show you how to configure and use the high-speed camera. Below are some things you will need to take into consideration when setting up. To assist you here are some short videos showing how to use the camera. text/html 2026-02-10T21:15:21+00:00 Anonymous (anonymous@undisclosed.example.com) https://physlab-wiki.com/phylabs/lab_courses/phys-211-wiki-home/drop-pinch-off/expected-powerlaws?rev=1770776121&do=diff For this experiment we want to investigate how the shape of the neck of a drop changes through out the pinch off process. Fluids are complex systems which can be difficult to characterize in terms of fundamental physics principles. But with a little bit of knowledge of some of the basic parameters of fluids, we can use the technique of dimensional analysis to predict possible relationships among the processes which are most likely to be involved in driving the behavior which we observe.$[\gamm… text/html 2022-04-15T11:59:21+00:00 Anonymous (anonymous@undisclosed.example.com) https://physlab-wiki.com/phylabs/lab_courses/phys-211-wiki-home/drop-pinch-off/high_speed_fluid_dynamics?rev=1650038361&do=diff Interesting Fluid Dynamics Glycerin dropping into water A drop of glycerol falling from a medium height into water. A drop of glycerol falling from a low height into water. A drop of glycerol falling from a high height into water. Isopropol alcohol spray from a nozzle text/html 2024-10-30T15:44:40+00:00 Anonymous (anonymous@undisclosed.example.com) https://physlab-wiki.com/phylabs/lab_courses/phys-211-wiki-home/drop-pinch-off/imagery?rev=1730317480&do=diff Video clips Two different video clips of the drop pinch off process recorded with a high speed camera running at several thousand frames per second. When watching through them keep in mind that the whole process took less than a second. Play through them at normal speed, then go back and lower the playback speed (controls are accessed via the three dots in the lower right corner of the frame) and slowly watch the process. The first video is of a water drop. The second is pure glycerin. Although… text/html 2026-03-18T15:15:50+00:00 Anonymous (anonymous@undisclosed.example.com) https://physlab-wiki.com/phylabs/lab_courses/phys-211-wiki-home/drop-pinch-off/marks-final-notes?rev=1773861350&do=diff Marks Final Notes - Drop Pinch Off Core principle of the Drop Pinch Off lab which must never be violated. Automation of any part of the lab is bad. Very bad. Camera Notes The camera does not support autofocus. Autofocus is the last thing we would want anyway because it would focus on pretty much everything in the field of view except for the precise location on the drop we are interested in. Additionally, pushing a button to achieve focus means the students would never look at nor think a… text/html 2026-02-12T15:44:32+00:00 Anonymous (anonymous@undisclosed.example.com) https://physlab-wiki.com/phylabs/lab_courses/phys-211-wiki-home/drop-pinch-off/start?rev=1770929072&do=diff Drop Pinch-Off Autumn 2025 TA Notes The formation and pinch-off of a drop is governed by a myriad of fluid physics phenomena. With the help of high-speed photography, we can study different stages in the evolution of a drop and gain insight into the length and time scales over which different forces dominate. This experiment uses dimensional analysis to provide potential models for the narrowing radius of a drop's neck nearing pinch-off, and tests these models against data collected in differ… text/html 2026-01-15T14:14:02+00:00 Anonymous (anonymous@undisclosed.example.com) https://physlab-wiki.com/phylabs/lab_courses/phys-211-wiki-home/drop-pinch-off/ta-notes-2026?rev=1768504442&do=diff TA Notes for Drop Pinch Off Lab Day 1 The purpose of the Day 1 activity is for students to learn how to operate the camera, take and analyze data, and most importantly how to think through an investigative experiment where you make decisions on what to do next based on looking at your data. text/html 2026-01-15T11:13:06+00:00 Anonymous (anonymous@undisclosed.example.com) https://physlab-wiki.com/phylabs/lab_courses/phys-211-wiki-home/drop-pinch-off/ta-notes-pre2025?rev=1768493586&do=diff Notes for the TA regarding the Drop Pinchoff experiment. ---------- Points of emphasis for the experiment. * Experimental research can be exploratory or discovery based. As opposed to testing models or theoretical predictions, or making precise measurements of a specific quantity like the mass of the Higgs boson. text/html 2024-06-11T16:34:46+00:00 Anonymous (anonymous@undisclosed.example.com) https://physlab-wiki.com/phylabs/lab_courses/phys-211-wiki-home/drop-pinch-off/video-conversion?rev=1718138086&do=diff Video conversion In order to read the videos from the camera into ImageJ (aka. FIJI) it is necessary to convert them from the MPG4 codec to an older AVI codec. Doing so involves using the command line in a cmd window. Converting an mp4 movie file into an avi file