Bullet Velocity Experiment: Does a Fired or Dropped Bullet Hit the Ground First?

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Discussion Overview

The discussion revolves around the question of whether a bullet fired horizontally from a gun or a bullet dropped from the same height will hit the ground first. Participants explore this question under various conditions, including the effects of air resistance and the orientation of the bullets.

Discussion Character

  • Exploratory
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants assert that if both bullets are released simultaneously in a vacuum, they will hit the ground at the same time, as gravity acts equally on both.
  • Others argue that when air resistance is considered, the outcome may vary depending on the orientation of the dropped bullet and other factors.
  • A participant mentions that Earth's curvature and rotation could complicate the scenario, although this may be negligible for short distances.
  • One participant uses the second equation of motion to suggest that both bullets will take the same time to hit the ground, given that their initial vertical velocities are the same.
  • Another participant proposes that the launch angle of the fired bullet could significantly affect its drop time, indicating that a slight angle could lead to different results.
  • One participant claims that due to non-linear air resistance, the dropped bullet should hit the ground first.

Areas of Agreement / Disagreement

Participants do not reach a consensus, as multiple competing views remain regarding the effects of air resistance and the conditions under which the bullets are released.

Contextual Notes

Limitations include the dependence on assumptions about air resistance, the orientation of the bullets, and the potential impact of external factors like Earth's curvature and rotation.

RandyD123
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If a bullet is fired from a gun perfectly parallel to the ground and a bullet is dropped from that same height at the same time which one hits the ground first?

Sorry for the two late edits. 1. The gun is not dropped, the gun is locked in a vice and perfectly level to the ground. 2. The bullet in your hand is released at the end of the gun barrel and just dropped.
 
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RandyD123 said:
If a bullet is fired from a gun and a bullet is dropped from that same height at the same time which one hits the ground first?

I guess it depends which way the gun is pointing. If you fire at the ground that bullet will get there first.
 
If the bullet is fired perfectly horizontally, the gun is dropped at the exact same time, and if wind resistance is neglected (i.e. doing this in a vacuum), then they will both hit the ground at the same time.

(well, neglecting the shape of the gun--in a real gun, the handle would hit the ground first, but the bullet comes out of the barrel, so it has a longer distance from the ground)
 
Previous posts seem to have misunderstood the question. In a vacuum both bullets would hit the ground at the same time.

When air resistance is taken into account it depends on the orientation of the dropped bullet, as well as other factors. I wouldn't try to guess the net result.
 
RandyD123 said:
If a bullet is fired from a gun perfectly parallel to the ground and a bullet is dropped from that same height at the same time which one hits the ground first?

Sorry for the two late edits. 1. The gun is not dropped, the gun is locked in a vice and perfectly level to the ground. 2. The bullet in your hand is released at the end of the gun barrel and just dropped.

Who needs PF when you've got YT:

 
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mathman said:
When air resistance is taken into account it depends on the orientation of the dropped bullet, as well as other factors.
Earth's curvature and rotation make it even more complicated. But for short ranges this can be neglected.
 
The direction in which you require the time is vertical. Initial velocities of both the particles in the vertical direction is same that is 0.Equal amount of acceleration acts in the vertical direction that is g. No other forces act on the vertical direction. Using 2nd equation of motion in the vertical direction, s=1/2gt2 (as u=0),t comes out to be equal as s and g are same in both the cases.
 
PeroK said:
Who needs PF when you've got YT:


The difference in arrival time can easily (?*)be explained in terms of the actual launch angle of the fired bullet. A degree up or down would represent a significant difference in drop time for the fired bullet. I wasn't clear as to how they got their launch elevation to be zero - in the end, the best method would probably to do the experiment the other way round and use the synchronous landing to get the launch horizontal.
*The sums are easy for someone with time to spare.
 
RandyD123 said:
If a bullet is fired from a gun perfectly parallel to the ground and a bullet is dropped from that same height at the same time which one hits the ground first?

Due to the non-linear air resistance the dropped bullet should hit the ground first.
 

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