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Scott H June 22, 2011 at 1:24 pm

Yes there is. Take a look in Roark &Young’s Formulas for “Stress and Strain”. There are four equations (one from the wall to the start of the load, one for the deflection across the load, and one for the deflection from the end of the load to the end of the beam, and one for the maximum deflection of the beam) and are too difficult to write here.

Susan C-2 June 23, 2011 at 1:25 am

She’s trying to make her friend feel good. She sounds like a great girl…

dental_hygienist June 23, 2011 at 1:46 pm

Yes, your speech will be affected at first. It will take a week to a month for you to figure out how to speak normally again. It just takes some getting used to, but you will get used to it. It will not permanetly affect your job. Be sure you ask for wax. Your lips and tongue might get cut up at first, but they can give you this clear wax to pack onto the rough parts of your braces. It’s a life saver.Don’t worry too much about it. So many people get braces and so many adults are having them put on now. Just don’t be in too much of a hurry to get them off…don’t pressure your orthodontist that way because moving the teeth too quickly in adulthood can lead to bone loss. Just something to be careful of. Oh, get a waterpik…that’s just advice from a hygienist. Flossing with braces is a pain and very time consuming so if you don’t think you’re going to floss, then you must get a waterpik. It’s essential! Trust me.I hope this helps.

minorchord2000 June 24, 2011 at 1:37 am

Look in Roark’s again because there is a section on rings which includes the deformation under load.

billrussell42 June 24, 2011 at 1:52 pm

simple calc, 1/10 of 0.0090 (9mΩ)Voltage sensitivity is E = IR = 10* 0.0090 = 0.09vNew R = E/I = 0.09v/100 = 0.0009 ohm (0.9mΩ)but that is total R, including the original R.Req (mΩ) = (9*.9)/(9-0.9) = 1mΩ.

Marcus June 25, 2011 at 1:15 am

Now the problem lies in the fact that the point load is at any point. There really is no easy formula, you can use superposition but it will be difficult to get the max moment via that method. The reason for this is that the max moment from the udl is at the mid span and the max moment from the point load is at the point load. Don’t recommend this method.I recommend to draw out the FBD and calculate the shear and moment diagrams, and read the max moment off of that. If your not sure how to do this use the worst case scenario udl w/ the point load mid span, it will be Conservative but still safe. How conservative depend on the location of the point load.use: wL^2/8 + PL/4 = MmaxDeflection is a different problem but similar, their are a few methods but they can be quite complicated.My recommendation is to go Conservative worst case, if you are not sure how to use these other methods:5wl^4/384EI + Pl^3/48EI = max def.Sorry there is really no easy formula for deflection but max moment shouldn’t be too hard to find using the FBD’s. If you add details about the beam in question someone could calculate it out for you. GL

Matt June 25, 2011 at 1:16 pm

For differently shaped beams the moment of inertia, I, will change. I’ve never seen that formula exactly like that before, so I’m assuming it’s for a specific loading condition.

debydete June 26, 2011 at 1:16 am

The E-field will exert a horizontal force “qE” ,which will cause the ball to swing up to some angle “@”, where it will stop and hang in equilibrium.The forces on the ball are then its weight “mg” (down) ,the horizontal electric force “qE” and the string Tension “T” up along the string. T makes the same angle “@” with the vertcal as the string.Now just get x & y components of “T” and apply the equilibrium condition in each direction;TSin@ = qETCos@ = mgDivide eqs to elliminate “T”Tan@ = qE/mgYou are given everything necessary to find the right side. Then take ArcTan.Don’t forget to change mass to Kg.

RayHere June 26, 2011 at 1:46 pm

This tactic is only effective on liberals So why not use it on them?

Huh? June 27, 2011 at 1:03 am

lol i believe you are in 4B Physics Lab at city college san franscisco

krk June 27, 2011 at 1:21 pm

a.280k b.277k.

civil_av8r June 28, 2011 at 1:04 am

The dimensions and material increase deflection)From Hooke’s Law: Strain = E*stress.Different materials have different Young’s Modulii, so the material does effect the deflection.Stress is usually given as stress = M*c/I And I is the moment of inertia of the cross section. So a different cross section will yeild a different stress which will yield a different strain.The position of the weights.)The further weights are from the attached end the larger the moment is at the supported end. So the further out they are, the more deflection will occur.The length of cantilever.)The length of the lever doesn’t reall matter only if you take into account the weight of the lever. The placement of the load is the bigger factor.The temperature.)The temperature effects the length of the lever since the hotter it is the longer the lever will become thereby increasing the lever arm of the load. If the temperature gets hot enough it can effect the internal strength of the material.