How do I calculate physics formulas containing derivatives and real numbers?

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SUMMARY

This discussion focuses on calculating impulse in physics using derivatives, specifically when a force of 10N is applied. The relationship between momentum change (dP) and net force (Fnet) is established through the equation dP/dt = Fnet, leading to the integral form Δp = ∫F(t) dt for average force over time intervals. Participants emphasize that collisions cannot occur in zero time, and the concept of instantaneous change is addressed through calculus, highlighting the importance of finite time intervals for accurate calculations.

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  • Understanding of Newton's laws of motion
  • Familiarity with calculus concepts, particularly derivatives and integrals
  • Knowledge of impulse and momentum equations
  • Basic grasp of force measurement in Newtons (N)
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  • Study the principles of impulse and momentum in physics
  • Learn about the application of calculus in physics, focusing on derivatives and integrals
  • Explore numerical methods for approximating force over time intervals
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Students of physics, educators teaching mechanics, and anyone interested in the application of calculus to physical problems involving force and motion.

NODARman
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Hi, I'm trying to calculate my own physics problem but didn't get it something.
When I'm trying to calculate the impulse of the object when it's hit by F=10N force in the smallest possible time, then should I write:
dP/dt = Fnet => dP = Fnet*dt ?

Another question: In general, if I calculate just a net force, we know that the derivative of the constant is zero. Then if dP is 10 N/s and t->0 therefore Fnet = 10/0 ?
What I don't get is how to calculate any physics formula which contains derivatives and real numbers.
 
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I don’t think any collision actually lasts 0 seconds. A collision that lasts 0 seconds is a collision that doesn’t actually happen.

Also ##dP## would have units of ##N \cdot s## not ##\frac{N}{s}##.
 
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These might help

and if ##\dfrac{\mathrm{d}p}{\mathrm{d}t} = F(t)## then ## \displaystyle \Delta p = \int_{t_1}^{t_2}F(t) \mathrm{d}t##
Now one can define the average constant force of impulse as ##<F> = \Delta p / \Delta t = \Delta p / (t_2 - t_1) ##
i.e. ## \displaystyle <F> = \dfrac{1}{t_2 - t_1} \int_{t_1}^{t_2}F(t) \mathrm{d}t## which you might remember from calculus class.
 
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NODARman said:
What I don't get is how to calculate any physics formula which contains derivatives and real numbers.
You could take a calculus course?
 
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NODARman said:
When I'm trying to calculate the impulse of the object when it's hit by F=10N force in the smallest possible time
There's no such thing as the smallest amount of time. Unless you mean zero, in which case no collision occurs. The collision must last for some nonzero amount of time, however small.
 
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NODARman said:
Homework Statement:: .
Relevant Equations:: .

What I don't get is how to calculate any physics formula which contains derivatives and real numbers.
You should not feel bad, it took a fellow named Newton to figure out how to deal with instantaneous change.
To any degree of approximation for a well behaved force, slicing time into finite intervals Δt, assuming the force is constant over that interval and summing will get you a numerical result to nearly any level of accuracy required.
But doing the clever stuff like calculating exact orbits for all time requires a leap of intuition. What happens to this rate of change as I slice time into infinitesimal pieces (dt) ?? The answer is called The Calculus and it is a touchstone for human ingenuity. It is not easy.
 
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