Al Tobias (wat4y) - Office: Gibson S123 & Physics 218, (434) 924-0538
Demonstrations are cataloged according to PIRA Bibliography
PLEASE REQUEST DEMOS WELL IN ADVANCE
Due to Physics Building renovations, the lead time to set up demo requests has increased due to the need to transport equipment across campus. Please be kind and let me know well ahead of time what you need.
Choose a Topic or Enter a keyword to search:
You have selected the following Demos:
video - Ballistics Cart
Purpose:"Relativity Cart" Shoot Up & Drop In Moving Cart - to show that vertical motion in a moving inertial reference frame is curved motion when viewed from a stationary reference frame.
Procedure:We have three versions of this demo. The PASCO Ballistics Cart, the Arbor Scientific Ballistics Car and our original in-house built relativity car. When requesting this demo, you will get the PASCO Ballistics Cart by default (two such setups in stock).
1. PASCO Ballistic Cart: Level aluminum PASCO track on lecture hall bench with foam-wood barrier clamped to far end to prevent track/cart from falling off edge. The Ballistic Cart Accessory contains a trigger (ball launcher photogate). Verify photogate is aligned with trip bracket. First turn on switch, then insert ball into launcher and press down. Cart is now armed and ready for demo. Here are three possible senarios:
CONSTANT VELOCITY ON HORIZONTAL PLANE - with leveled out track
ROLLING DOWN INCLINED PLANE - with single 10cm block to tilt track
ACCELERATING ON HORIZONTAL PLANE - 2.16m string, 100g mass, pulley
2. Arbor Scientific Ballistics Car: This car rolls on its own wheels independent of a track. The steel ball bearing is launched from its canon via a pull-string.
3. Original In-house Relativity Car: Place the track on the lecture table and level. The ball bearing is loaded by pushing it all the way down and locking it in place with the small trigger on the bottom of the car. With the ball bearing pushed in with the loading stick, reach under the car and pull the trigger forward until it catches. The firing mechanism should be adjusted so it will catch the trigger when the car passes over it. Some practice is required to get the speed right as it does not work too well when going too fast or slow.
Hints:Use the PASCO Ballistic Cart setup for best results.