# Recent content by cdummie

1. ### Amplitude of oscillations

Ok, let's see, N will be zero when gravity loses it's effect on the sand, which means, when velocity of the sand (along with the membrane) is such, that it's acceleration is equal to gravity acceleration, just with opposite direction. Is that right?
2. ### Amplitude of oscillations

So when ##a_m-g<0## they diverge, since ##a_m=-Aω^2sinωt## it means that ##-Aω^2sinωt<g## but what i am supposed to do next, we will have maximum velocity at equilibrium point, since after reaching equilibrium point it begins slowing down, right? Now, i should, as you said, use maximum velocity...
3. ### Amplitude of oscillations

Maybe when they reach equilibrium point, but i am not sure, could you explain it to me?
4. ### Amplitude of oscillations

Oh, that's what you meant, i didn't knew it's called vertical displacement function, i always refer to it as elongation in function of time, anyway, what's with the starting phase, is it zero or what?
5. ### Amplitude of oscillations

I am sorry but i don't know how to transfer frequency into vertical displacement function. Can you help me with that?
6. ### Amplitude of oscillations

Homework Statement A little amount of sand is spilt over horizontal membrane that oscillates with frequency f=500Hz in vertical plane. If sand grains are jumping to the height h=3mm with respect to the equilibrium position, find amplitude of oscillation of membrane. Homework Equations ω=2πf...
7. ### Frequency of wire oscillations

Ok, let's see if i understand this now. This is the same image i posted before, it just has that one angle labeled. If force that is straining this wire is F and it is acting both from the left and right part of wire, then the net force that is acting is sum of those two forces along the...
8. ### Frequency of wire oscillations

I don't understand you very well, why is restoring force (if by restoring force you mean the force that tries to return wire to original position) is twice the component of the tension in the wire?
9. ### Frequency of wire oscillations

This is all i have, i don't know how to draw force F, force F1 is the force that pulls the pellet out of equilibrium position. How can i draw the force that strains wire?
10. ### Frequency of wire oscillations

Homework Statement There's a horizontal thin wire whose mass is negligible and whose length is l=1m. It is strained with constant force F=10N. If we place a tiny pellet in the middle of wire (mass of pellet is m=1g) and then we bring wire out of equilibrium position (moving out of it's original...
11. ### Total magnetic moment of simple system.

That's exactly what i thought, it might be that they meant a torque on the magnetic moment, but i wasn't completely sure. Anyway, i needed approval that i can't determine m by using the fact that i know B, i mean, that there's no formula that is used to determine m by knowing B.
12. ### Total magnetic moment of simple system.

Homework Statement If there's a current I flowing through the rectangular conductor and it's located in the magnetic field in such way that normal vector of the surface that this rectangle forms closes the angle of 60 degrees with magnetic induction vector find total magnetic moment of this...
13. ### Two coils of wire with the same size and shape

Thank you for your help. I'll check out that "Insight" paper of yours.
14. ### Two coils of wire with the same size and shape

I've tried to find that more basic definition of k in my books and notes, but i couldn't, but i found something that can be related to this problem, i found out that if whole flux through first coil goes through second coil (through it's cross section to be precise) that then we have perfect...
15. ### Magnetic field of a ferromagnetic cylinder

But there are magnetic surface currents here, right? What about them?