Recent content by NooDota

Yeah, how exactly does it go back to m*g*h? Is there any other way? The only reason I'm asking is because I'm curious, that's all.

Homework Statement In a physical, or a simple pendulum, to get the velocity of the pendulum at some point, we apply the kinetic energy theory, and use m*g*h to calculate the work done by weight, I'm wondering if there are any other ways to calculate the work? I don't care how complicated it...

Okay, thank you. So increasing the frequency leads to increasing the tension forces?

How is x not a function? F(x)=x? Yeah, but what's the relation between lambda and the period? K=2pi/lambda and W=2pi/period, I don't see the relation between the two. Thank you. Consider now a wave of arbitrary shape, given by y(x, t)= h(kx+- wt) where h represents any function, the sine...

> No. It cannot depend on x like that. Why not? "x" is a function. It has x and t, so it's a wave function, no?

Homework Statement Hello, I've recently started learning about waves, and there are a few stuff I don't understand (I'm talking about transverse waves):1. What function describes the movement of a single "element" on the string? I mean an element in which only its y changes, but x remains...

Teacher considered the 10cm displacement to be caused by both weight and EM force and said to scrap the "before current is turned on" part. But even then I'd still solve it the same way I did first, whatever.

It's a multi task problem with several questions, the first ones are all about electromagnetic stuff and no mechanics involved, I copied the mechanics part but forgot to add the mass (didn't think it's relevant). Yes, the wording is indeed confusing, the way I understood the last sentence is...

Okay, nevermind, I figured out how they reached 30, although my answer seems more correct to me than their, I'm sure people here can tell which answer is correct. What the teacher did: (M is 1/5 KG) Forces affecting the bar: W + Fs0 + F(electromagnetic) =0 Axis is directed downwards W - Fs0...

No idea, I only talked briefly to him, I'll ask him again tomorrow and he should explain it fully. (Other students also got 30 somehow). Yes, I copied it correctly.

Okay, I asked my teacher and he said you don't consider X0, you only take the displacement caused by the electromagnetic force, not the weight. His answer was k = 30 I don't really get it, can someone explain what I did wrong and what I should have done?

So the answer's correct? Never really thought about checking if the values make sense.

Fs0 is the spring's pull on the bar, and Fs'0 is the bar's pull on the spring, x0 is the initial stretch, x is the stretch after the current is turned on, you can just ignore what I said about the normal force. What I did was apply Newton's second law to the bar only after the current was...

Homework Statement We take a horizontal copper bar with length of 20cm and attach it from the middle to a vertical spring which mass is neglected and has a spring constant K, we apply a horizontal magnetic field with magnitude 1/2 T and have a 10A current run in the copper bar. The bar rests...

It just ends up being the same numbers as before? It doesn't make a difference if you add it or not?