This apparatus can be used to demonstrate that in a vacuum bodies of different density or mass fall at the same speed. It consists of an acrylic tube fitted with bungs at one end.
A valve with stopcock at one end allows a vacuum pump to be attached, and the air evacuated from the tube. Inside the tube is a coin, and a piece of paper. When air is in the tube, the coin falls quickly but the paper is subject to air resistance and falls more slowly. With the air evacuated, the only force acting is gravity, so the two fall at equal rate, despite the difference in weight.
A. Hi Andrew, thank you for your question. The product details states acrylic tube.
Reviews
Guinea & Feather Demonstration Improvements.
Reviewed by: Andrew Goloskof - 13 December 2018
Well, we got ours working after a few essential tweaks…
The supplied silicone tubing collapses on itself as you start evacuating the air from the tube preventing complete air extraction, so it was replaced with the correct hard vacuum tubing.
Due to static build up on the polycarbonate tube the tissue ‘feathers’ simply adhered to the sides (remember that tissue paper is used in static electricity experiments), having tried aluminised Mylar film and aluminium foil which all failed, we eventually found some real feathers from a corvid, once washed and degreased and thoroughly dried, they worked perfectly. As it stands, the basic kit will not perform the desired task correctly. It is now being used as I type this review.
Works really well
Reviewed by: Peter Sigsworth - 14 November 2018
Once evacuated the pieces of paper drop at the same rate as the weight (the paper initially stuck to the sides but the evacuation process removed any static and the paper worked fine after that)
