Does a Bullet Speed Up After Being Fired?

In summary, the speed of a bullet does increase after leaving a gun if it's fired downhill in a vacuum. However, in most cases, it does not continue to accelerate as it has already reached its maximum velocity. This concept also applies to other objects such as a cricket ball or a van, where the initial acceleration is followed by deceleration due to external forces such as drag and suspension. Other factors, such as body pitch and the release of brakes, can also create a false sense of continued acceleration.
  • #1
CharlesF
2
0
Does a bullet speed up after leaving the gun?
 
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  • #2
If it's fired downhill in a vacuum, yes. Otherwise, no.
 
  • #3
We got this exact question a month or so ago - where is this coming from, Charles?
 
  • #4
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.
 
  • #5
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.
 

1. How does a bullet accelerate after being fired?

When a bullet is fired from a gun, it is propelled by the expanding gases from the gunpowder explosion. This creates a force that pushes the bullet forward, causing it to accelerate in the direction of the barrel.

2. Does the speed of the bullet change as it travels through the air?

Yes, the speed of a bullet changes as it travels through the air. Initially, the bullet will have a high velocity due to the force of the gunpowder explosion. However, as it moves through the air, it will experience air resistance which will gradually slow it down.

3. What factors affect the speed of a bullet after being fired?

The speed of a bullet after being fired is affected by several factors, including the type and amount of gunpowder used, the weight and shape of the bullet, the length of the barrel, and the amount of air resistance it encounters as it travels through the air.

4. Is there a maximum speed that a bullet can reach?

Yes, there is a maximum speed that a bullet can reach. This is known as the terminal velocity, which is the point at which the force of air resistance is equal to the force of gravity acting on the bullet. At this point, the bullet will no longer accelerate and will maintain a constant speed as it continues to travel through the air.

5. Can a bullet speed up after being fired if it encounters other objects?

Yes, a bullet can potentially speed up after being fired if it encounters other objects. This can happen if the bullet ricochets off a surface or if it passes through a medium with a different density, such as water. However, the speed increase will be minimal compared to the initial acceleration from the gunpowder explosion.

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