|MadSci Network: Engineering|
Hi Jeffrey Well If I were you I’d use a spring. We compress it to the bottom of the launcher tube. Here it is held by a simple trigger. We release this trigger to fire the ball. Ping pong balls are very big for their weight. So air resistance is very important and makes calculation what you will hit very difficult. Start with the tube inclined at 50 degrees from the horizontal and do some experiments. With a table-tennis bat you can hit the ball 5 meters. So your spring will have to give the ball that much speed. If you are trying this out-of-doors, any wind will make results highly unpredictable! John
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