Will the Bullet Hit the Monkey If It Doesn't Jump?

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    Paradox
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Discussion Overview

The discussion revolves around the classical monkey and hunter paradox, specifically addressing whether a bullet will hit a stationary monkey if it does not jump. Participants explore the implications of gravity on the bullet's trajectory and the necessary adjustments a hunter must make when aiming at a target under different conditions.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant questions if the bullet will hit a stationary monkey, suggesting that the hunter may need to aim higher due to the bullet's parabolic trajectory in a gravitational field.
  • Another participant argues that in a zero-gravity environment, a hunter would hit a stationary target, contrasting this with the situation on Earth where gravity affects the bullet's path.
  • Some participants discuss the necessary information for calculating the correct angle to aim, including bullet velocity and the height of the monkey.
  • There is mention of the practice of "sighting in" a rifle, which allows hunters to adjust for bullet drop based on distance and other factors.
  • One participant highlights that even with a bullet drop of 5 cm over a distance of 100 m, this could significantly affect accuracy, raising questions about how shooters without physics knowledge manage to hit their targets.
  • Another participant shares personal experience with sighting rifles, noting that ideal ranges and adjustments depend on various factors such as muzzle velocity and environmental conditions.
  • Humorous remarks are made regarding the challenges of measuring muzzle velocity and the fleeting nature of the monkey in a practical scenario.

Areas of Agreement / Disagreement

Participants express differing views on the impact of gravity on bullet trajectory and the adjustments needed for accurate shooting. There is no consensus on how a hunter should aim in relation to the monkey's position, and the discussion remains unresolved regarding the practical implications of these concepts.

Contextual Notes

Limitations include assumptions about the environment (gravity vs. zero gravity), the precision required for hitting a target, and the varying levels of experience among hunters. The discussion does not resolve the mathematical steps involved in calculating the necessary adjustments for bullet drop.

damitr
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The classical monkey and the hunter paradox goes something like this :

A monkey sitting on a tree top is aimed at by a hunter. As soon as hunter shoots the monkey jumps down. The bullet hits the monkey even when it has jumped because they both fall with same acceleration viz. g.

My question is:

If the monkey does not jump, will the bullet still hit him?
Does the hunter have to aim a little higher to get the correct shot?
 
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If a hunter aims at a stationary target in a zero-gravity enviorment, he will hit the target.

If a hunter aims at a stationary target on earth, then the bullet will follow a parabolic descending trajectory, like any falling object; (of course it will be very slight - the forward velocity will at any time be orders of magnitude greater than the downward velocity). Thus he will miss the target - the bullet will have fallen slightly and will hit below target.

Has this answered your questions?
 
Ok
The hunter misses the target in gravity, but then how does one get a correct shot?
 
Given the necessary information you can compute the angle needed. What Information do you thing you need?

You can always do it by trial and error. This would correspond to the practice called "sighting in" used by people who shoot rifles.
 
The information needed would be the velocity of the bullet as it leaves the rifle, height at which the monkey is present.

I was unaware of the practice of ''sighting in''. But does that mean an experienced hunter can miss a target, if the location of hunting changes (changing the g value)?
 
In practice, if the target is not far away, the distance over which the bullet falls (as compared to go in a straight line) is rather small.

To give you an idea, assuming the velocity of the bullet is ~1000m/s, and the target is 100 m away, this will take the bullet 0.1 s to reach the target. In 0.1s, it will also fall g t^2/2 = 0.05 m = 5cm.

cheers,
Patrick.

PS:

http://hypertextbook.com/facts/1999/MariaPereyra.shtml
 
5 cm is quite an high value when the precision is concerned...then how does an shooter who doesn't know any physics will make it..if ofcourse he has 1 shot.
 
heman said:
5 cm is quite an high value when the precision is concerned...then how does an shooter who doesn't know any physics will make it..if ofcourse he has 1 shot.

And he's hunting mice :smile:
 
I've done some shooting and sighting in. Idealy you want to sight in a rifle such that a flat horizontal shot will rise ever so slightly as it leaves the gun. In this manner you can split the inaccuracies to fall either above or below your target depending on the distance. For instance if you sight a 30-30 to hit dead on at ~100 yards then depending on the target distance less than ~100 yards it can hit ~1 inch above or below the intended target. Generally speaking your inaccuracy is half of the bullet fall within the ideal range it is sighted for. Beyond that range accuracy drops off exponentially. Ideal ranges are determined by things such as mussel velocity, loss of velocity due to resistance, bullet rotation, bullet aerodynamics, and windage. 30-30s don't work exactly as expected by the physics for these reasons but generally all rifles are sighted to split the difference for an ideal maximum range.

Oh the question.. Sighted this way if the monkey jumped you miss unless the monkey was outside the intended range of the rifle.
 
Last edited:
  • #10
heman said:
5 cm is quite an high value when the precision is concerned...then how does an shooter who doesn't know any physics will make it..if ofcourse he has 1 shot.
A hunter who plans on shooting at things 100 yds away or more must account for the drop, though whether they understand the physics behind it is another matter.

I don't have a lot of experiece with rifles, but I used several when I was in the Navy and all had distance compensation on their open sights. It was precalculated, so all you had to do was dial-in the distance and that raised the rear sight the appropriate amount.
 
  • #11
my_wan said:
Ideal ranges are determined by things such as mussel velocity...

It is the mussel velocity that always messes me up. By the time I've run down to the beach with a measuring tape and a calendar, and back again, the monkey is invariably gone.
 
  • #12
DaveC426913 said:
It is the mussel velocity that always messes me up. By the time I've run down to the beach with a measuring tape and a calendar, and back again, the monkey is invariably gone.
:smile: :smile: :smile: Too funny.
 

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