You'd get a very strong puff of air. The air leaving the end of the barrel doesn't have a lot of momentum so it diffuses pretty quickly in the ambient air. You could shape the outlet to get a more focused jet, but it's still going to be a puff, not a strong sustained stream.
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I want to see what happens when they forget to include the ball in the experiment.
You'd get a very strong puff of air. The air leaving the end of the barrel doesn't have a lot of momentum so it diffuses pretty quickly in the ambient air. You could shape the outlet to get a more focused jet, but it's still going to be a puff, not a strong sustained stream.