Conservative Force and Potential Energy

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Flipping Physics

Күн бұрын

Пікірлер: 29

@aasimali6937 3 жыл бұрын

Your videos are very interesting and keep the interest in the subject to the top. Thank you Mr. P.

@Hanuman120 4 жыл бұрын

Looks good. I think the definition you are using for an integral is one that is fine to use at the beginning as students are learning about it, but I don't love using that definition, since it relies on a graph. It makes sense to use that definition in abstract math, but it's kind of like saying that the product of any two quantities is finding the area of a rectangle (which I suppose you can always construct a rectangle for that). For this example, I think it makes more sense to say we're adding up little bits of work as we move along the path.

@FlippingPhysics 4 жыл бұрын

Thanks for looking it over. How would you prefer to describe going from derivative to integral as I do in this video?

@Hanuman120 4 жыл бұрын

@@FlippingPhysics I'll give it some thought.

@Hanuman120 3 жыл бұрын

@@FlippingPhysics I would probably say that an integral is an infinite sum of infinitely small quantities (that adds up to a finite value). In this case, it's adding up all the small bits of work, dW. For one individual dW, the object moves through a small distance dx. Remember, W=F·x, so dW=F_x * dx. That's what we were adding up in the integral here! I think applying to physical intuition can help with understanding here, rather than abstracting, if that makes sense. Though, I suppose it makes the strategy slightly less generalizable. You could just say that the integrand is the small thing we're adding up iteratively. I tend to like to start from the constant form, then go to the infinitesimal form, so I would just start with dW=F_x dx. From there, it's an easy step to either the integral or derivative form. (Oh, and I suppose maybe use U instead of W, as I have, but I might just sub that out at the end.)

@FlippingPhysics 3 жыл бұрын

I see your point. I have always preferred the rectangle approach, however, I can see the utility of this approach as well. Thanks.

@Hanuman120 3 жыл бұрын

@@FlippingPhysics Yep. I do appreciate the graphing approach, since it may be more familiar to students. But when you're doing any coordinate transforms, it gets challenging to visualize. Like for CoM or rotational inertia, you have a dm term. This can't really be expressed as a graph of x vs m.

@Pedritox0953 15 күн бұрын

Great video! I think that this formula that relates Potential Energy & Forces is the start point in Physics, Peace out

@FlippingPhysics 14 күн бұрын

You are welcome to peace out, but I hope you'll stick around for more physics!

@imaginenation5158 3 жыл бұрын

Thank you so much for doing the subtitles, it helps a lot

@FlippingPhysics 3 жыл бұрын

Glad the time spent adding those is worth it.

@aparnamp6300 3 жыл бұрын

sir please explain the electrostatic force and potential energy. in both moving a positive or negative charge in a field

@AyalaMrC 3 жыл бұрын

Other than having to pause it a couple times to put my calculus hat on, it looks really good. 8~)

@FlippingPhysics 3 жыл бұрын

I am glad you found your calculus hat!

@christianbonvang2141 3 жыл бұрын

Such a good teacher! thank you very much for your videos sir!

@FlippingPhysics 3 жыл бұрын

You're very welcome!

@oochipchoogi 3 жыл бұрын

hello! will the force be always negative or positive? i saw some videos excluding the negative sign which makes the Force positive.. can anyone help?

@carultch 3 жыл бұрын

The sign of the force will depend on the specifics of the problem, and how you assign your positive and negative direction. The reason for the negative sign in the general relation between force and potential energy, exists such that we can keep track of energy being stored in the form of potential energy when the force acts against motion, and energy released from the form of potential energy via work done by the force when the force acts with the motion. In Physics, the generalized relationship between conservative force F, and potential energy U, is F = -grad U, where grad refers to the vector calculus concept of a gradient. In 1-dimensional form, it reduces to F = -dU/dx, or U = -integral F dx.