How to find the path if we only know the velocity (without common formulas)?

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SUMMARY

The discussion centers on the challenge of determining the path of a moving particle when only its velocity function, v(t), is known over a time interval from t=a to t=b, without access to traditional formulas or methods. Participants concluded that while it may seem impossible to find the path without knowing how velocity is calculated, techniques such as Riemann sums can approximate the integral of velocity to estimate displacement. The conversation highlights the importance of calculus concepts in solving such problems, specifically the relationship between velocity and displacement.

PREREQUISITES
  • Understanding of velocity as a function, v(t)
  • Basic knowledge of calculus concepts, particularly integration
  • Familiarity with Riemann sums and their application in approximating integrals
  • Awareness of the concept of Dead Reckoning in real-world navigation
NEXT STEPS
  • Study the application of Riemann sums in calculus for estimating integrals
  • Learn about the fundamental theorem of calculus and its implications for velocity and displacement
  • Explore the concept of Dead Reckoning and its historical significance in navigation
  • Review Khan Academy resources on motion problems involving integrals
USEFUL FOR

Students of calculus, mathematicians, physicists, and anyone interested in understanding the relationship between velocity and displacement in motion analysis.

Mike_bb
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Hello!

I invented the problem and I try to solve it:

Let we only know velocity of moving particle: ##v(t)## from ##t=a## to ##t=b##. And we don't know about ##F(b)-F(a)## and other formulas. We can't use formulas directly.

How to find path from ##t=a## to ##t=b##? How to reason in this case?
Is this problem can be solved?

Thanks.
 
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Mike_bb said:
Hello!

I invented the problem and I try to solve it:

Let we only know velocity of moving particle: ##v(t)## from ##t=a## to ##t=b##. And we don't know about ##F(b)-F(a)## and other formulas. We can't use formulas directly.

How to find path from ##t=a## to ##t=b##? How to reason in this case?
Is this problem can be solved?

Thanks.
What's the general relationship between displacement and velocity?
 
PeroK said:
What's the general relationship between displacement and velocity?
Neither. We only know ##v(t)##.
 
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What is velocity?
 
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PeroK said:
What is velocity?
Thanks for your hint. I solved my problem!
 
Can you show us what you did?

It helps others following your thread to learn from your work.

Also, we might spot something in your solution that you hadn't considered.
 
jedishrfu said:
Can you show us what you did?

It helps others following your thread to learn from your work.

Also, we might spot something in your solution that you hadn't considered.
The task was: find path of moving particle if only velocity is known. But as I understood it's impossible if we don't know how velocity is calculated (using limit).
 
Mike_bb said:
The task was: find path of moving particle if only velocity is known. But as I understood it's impossible if we don't know how velocity is calculated (using limit).
Impossible? Surely not. In the real world there is a process that has been used for centuries. Dead Reckoning.

In the mathematical world we use a different term.
 
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Have you studied calculus in school yet? How much?
 
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DaveE said:
Have you studied calculus in school yet? How much?
I've studied calculus in school many years ago but forgot some things. I have several learning gaps.
 
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Mike_bb said:
The task was: find path of moving particle if only velocity is known. But as I understood it's impossible if we don't know how velocity is calculated (using limit).
If you are not allowed to use the standard approach $$ \vec s=\int_{a_1}^{b_1}\vec v(t)dt $$ try to solve the problem by using the Riemann sum which is an approximation of the integral. $$ \vec s\approx\sum_{i=1}^{n}\vec v(t_i^*)\Delta t_i $$ where ## \Delta t_i=t_{i}-t_{i-1} ##, ## t_{i-1}\le t_i^*\le t_i ##, ## t_0=a_1 ##, ## t_n=b_1 ##.
 
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  • #13
You are making up the problem and saying that we are not allowed to use any facts. That makes it difficult.
 

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