Does a Bullet Speed Up After Being Fired?

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A bullet does not speed up after being fired unless it is shot downhill in a vacuum; otherwise, it begins to decelerate due to drag. The discussion highlights a misconception about objects like bullets and cricket balls, which do not continue to accelerate once they leave the source of propulsion. Instead, they immediately start to decelerate because of air resistance. The sensation of continued acceleration in a vehicle, such as when shifting gears, can be misleading and is often due to factors like suspension dynamics rather than actual acceleration. Overall, once an object is no longer being propelled, it will start to slow down due to external forces.
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Does a bullet speed up after leaving the gun?
 
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If it's fired downhill in a vacuum, yes. Otherwise, no.
 
We got this exact question a month or so ago - where is this coming from, Charles?
 
I was driving my van the other day and i noticed that when i pressed the clutch into change to second gear the van seemed to continue accelerrate, with nothing powering it, just for maybe 1 second(or perhaps i imagined it).

That got me thinking about other things like bullets. Also does a cricket ball accelerate away from the bat with nothing pushing it, surely it can't get to it's return speed instantly.
 
In the case of a gun, there's still some pressure just as the bullet leaves the barrel, but this is a very short distance.

Once a ball leaves a bat, golf club, ... it no longer accelerates, and starts decelerating because of drag immediately.

In the case of a van, the suspension relaxing after acceleration mave give a rider a sense of continued acceleration, but the center of mass isn't accelerating. Sometimes the lack of deceleration force felt when braking then releasing the brakes, and car body pitch can give a false sense of acceleration as well.
 

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