Classical mechanics - hunter and monkey - frame of reference

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The discussion centers on the classical mechanics scenario involving a hunter and a monkey, where the monkey jumps as the hunter shoots. The key point is that the time it takes for the bullet to hit the monkey is the same in both the monkey's accelerating frame and the class's static frame, as time is invariant in Newtonian mechanics. The presence of gravity affects the paths of the objects but does not change the time of impact. While the monkey's acceleration complicates predictions in non-inertial frames, it does not alter the fundamental outcome of whether the monkey is hit. Understanding these principles clarifies the relationship between frames of reference and the laws of motion.
ethanhunt
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Hi,

This might sound very basic and but i am just starting to learn physics.
I an lecture by prof. walter lewin, he descibes the hunter and monkey scenario. The monkey jumps from the tree as soon as the hunter aims and shoot his gun. the bullet hits the monkey anyway.
In calculating the time it takes the bullet to hit the monkey, he calculates from monkey's frame of reference and class's frame of reference to be same. He also states that the time is same irrespective of a moving frame (monkey's) and static frame (Class).

My doubt is, the monkey is accelerating with respect to the class. So the time and speed of bullet should not be the same for both as one is accelerating. From what i understand, an accelerating frame of reference will not produce same results as relative velocities will differ.
Please let me know your thoughts on this. Am i missing something?

Thanks
EthanHunt
 
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What happens cannot depend on the frame of reference, whether accelerating or not. The monkey is either hit or not.

In Newtonian mechanics, time is invariant between different frames and so the time must also be the same in all reference frames. (This is different in relativity, but monkeys are not that fast.)
 
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Hi Orodruin,

Thank you for the explanation. I tried measuring the time taken when the 2 are only along the vertical and it does work out. So as i understand the presence of gravity only alters the path of the objects. As such the time taken is the same else the monkey does not get hit.

I think i understand. the non inertial frame concept affects the Newton's laws as seen in the non inertial frame of reference. The behavior will not conform to the laws.
So in Newtonian mechanics, both frames measure the time at the same rate but the cause / effect will not make sense. We cannot predict the behavior correctly.
 
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