How do I calculate the Impact Force of an object?

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Discussion Overview

The discussion revolves around calculating the impact force of an object, specifically one with a given mass and velocity, colliding with a solid target (the moon) in a vacuum. Participants explore the theoretical aspects of impact force, momentum, and impulse, while addressing the limitations of the provided information.

Discussion Character

  • Homework-related
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant expresses uncertainty about how to calculate impact force with only mass and velocity provided, emphasizing their lack of mathematical skills.
  • Several participants argue that the impact force cannot be determined without additional information, noting that the nature of the collision (solid target vs. gentle deceleration) significantly affects the force.
  • Another participant explains that while momentum can be calculated using the formula ##p = mv##, the force would theoretically be infinite if the object comes to rest instantaneously upon impact.
  • One participant suggests that calculating impulse, defined as the change in momentum, could be relevant, but acknowledges that the impact force remains undefined without further details.
  • A later reply questions the utility of knowing the impact force, suggesting that without context, the number would be meaningless.
  • Another participant reiterates the need for clarity on whether the question is a homework problem, indicating that it should be posted in the appropriate section if so.

Areas of Agreement / Disagreement

Participants generally agree that the impact force cannot be calculated with the information provided, and multiple competing views exist regarding the implications of the collision and the relevance of the calculations.

Contextual Notes

Limitations include the lack of information on the time of impact and the depth of the crater created by the collision, which are necessary for a meaningful calculation of force.

CitizenSentry
Okay so as you may have already guessed I'm really new to this site (as in I made my account about 2 minutes ago) and I'm really, really bad at maths so I need a lot of help with this question. I'm not even sure if this in the right sub-forum but if it isn't please relocate it to the correct one.
Anyway, the question as mentioned in the title is how do I calculate the Impact Force of an object.
I already have the velocity and mass of the object but that's it.
Okay the velocity of the object is 5,611,940m/s
the mass of the object is 294kg
I'm not sure whether this is important or not but the object is traveling through a vacuum.
Also If you do go out of your way to explain this to me, then please do so In a way similar to what you would with a child.
 
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You cannot - at least not with the given information. If the object hits a solid target it will lead to a large force (although "explosion" would be a more fitting description), if it is slowed down gently the force will be much smaller.

Homework-like problems should be posted in our homework section, but as this problem is impossible I don't think moving this thread would help.
 
mfb said:
You cannot - at least not with the given information. If the object hits a solid target it will lead to a large force (although "explosion" would be a more fitting description), if it is slowed down gently the force will be much smaller.

Homework-like problems should be posted in our homework section, but as this problem is impossible I don't think moving this thread would help.
The object in question is colliding with the moon at said speed (I'm assuming this due to the fact of the object being in a vacuum).
 
with mass and velocity of the object given you can calculate its momentum, ##p = mv##. All you need to know then is that force is the change in momentum per time. The problem is if we assume that the object hitting the moon comes to rest instantaneously the time it would take is ##t = 0s## and so the force would be infinite.

So you would have to make assumptions how deep the crater would be that the impact creates. You can eliminate the time from ##F = Δp/Δt## by substituting it with ##t = 2d/v##, where ##d## is the depth of the crater. So without any further information you can't say.
 
Marc Rindermann said:
with mass and velocity of the object given you can calculate its momentum, ##p = mv##. All you need to know then is that force is the change in momentum per time. The problem is if we assume that the object hitting the moon comes to rest instantaneously the time it would take is ##t = 0s## and so the force would be infinite.

So you would have to make assumptions how deep the crater would be that the impact creates. You can eliminate the time from ##F = Δp/Δt## by substituting it with ##t = 2d/v##, where ##d## is the depth of the crater. So without any further information you can't say.
I really appreciate the in-depth reply but I honestly don't understand a thing you just said, I'm really, really, hopeless at maths and my tutors don't make it any easier they don't care whether you learn it or not they're just there for the paycheck.
 
is it possible that you have to calculate the impulse? Impulse is the change of momentum. Momentum is, as already mentioned, the product of mass and velocity ##p = mv##. Since the velocity is ##0## after the impact the impulse is ##I = mv - 0 = mv##.
 
CitizenSentry said:
The object in question is colliding with the moon at said speed (I'm assuming this due to the fact of the object being in a vacuum).
If you knew the "force" of impact, what would you be able to do with that number?

Unless you have an answer for that question, it is pointless for us to try to provide you with a number for the force. It would be a meaningless large number that one could go "woo woo" over.
 
CitizenSentry said:
really appreciate the in-depth reply but I honestly don't understand a thing you just said, I'm really, really, hopeless at maths and my tutors don't make it any easier they don't care whether you learn it or not they're just there for the paycheck.
If this is a homework question, please open a thread in the homework section. Make sure to include the exact and full problem statement.

If it is not: With the given information the question doesn't have a meaningful answer, and further speculation what could be meant won't help. I closed the thread.
 

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