Recent content by Pir

Yes the pi can be factored out but DID YOU NOTICE THAT THERE'S ALSO A 1/PI, DICK? What happens with that?

What happens with the pi? And why isn't the x integrated with the rest? Shouldn't it be 1/2 x^2?

wrong

I don't understand, please write how to do it. You mean substitute x with u? That doesn't really change anything, there are still three factors.

Is that formula correct to begin with? I tried integrating by parts but I couldn't solve it. Please help by writing how to do it. I have a test in two days and I need to know how to solve this before then and it takes forever if I have to ask for one step at a time when there might be several...

Homework Statement Homework Equations X_{T} = \frac{1}{m}\int_{K}^{} x dmThe Attempt at a Solution I have decided a) and I got the volume to be ∏ volume units. I need help with b). I try to use the formula and I get this: X_{T} = \frac{1}{\pi}\int_{K}^{} 3\pi x sin^2xcosx dx But I need help...

Are you sure? 1/pi and pi will cancel out the pi. How do I calculate this then? And btw, could please not answer so short, I have a test in two days and I need to know this by then and it takes extremely long to solve just one task if I have to wait for the answer on every step. Please write...

So since rho = 1, mass is here the same as the volume. So then we get: X_{T} = \frac{1}{\pi}\int_{K}^{} 3\pi x sin^2xcosx dx Is this correct?

Aha, the moment varies throughout the body, not the mass, that makes sense. :smile: So the formula for XT will be X_{T} = \frac{1}{m}\int_{K}^{} 3\pi x sin^2xcosx dx How do we calculate this integral? m is unknown.

I know how to get to the formula X_{T} = \frac{1}{m}\int_{K}^{} x dm although here it is already given in the task. What I need help with is how to use it. First of all I wonder if - and if so, why - you are supposed to assume that the volume is varying inside the body, when you've already have...

I have decided a) and I got the volume to be ∏ volume units. I need help with b). I would need to have the physics of the problem explained. Please help me explain the physics, so that I from it can understand how to solve b). :smile: