Strength Definition and 1000 Threads

Hey guys, This may seem like an odd question but what would it entail to make an air compressor that can deliver 2000lbs of force? (I am not going to try and make one, don't worry :p ) When I say air compressor I mean any mechanism that runs on air. (Like an impact wrench) I ask this because...

Imagine the skyscraper and the very long rod placed on its top that rotates from horizontal position to upwards. http://img109.imageshack.us/img109/4817/fhfn.png I would like to know how is it possible to calculate/ascertain the maximal length and minimal width of the rod made of some...

I am looking to build a trapize style hanger that will be fabricated out of 2"x2"x1/4" cold formed steel tube 10'x4'x10' the shape is a U any idea where I can find the hanging weight of this type of hanger?

Hi, I'm a senior in high school trying to learn more about magnetism and magnetic shielding outside of my classes (I'm pursuing a degree in Materials Sciences at Penn State beginning this fall). I have been trying to determine a way to make a quantitative measure of a magnetic field's strength...

Hello, I design high powered rockets in our Tripoli rocket club. A particular plastic type of tube used is the Quantum 3.9 in dia plastic (sewer pipe) it is a thin wall design. http://www.publicmissiles.com/ They state that this basic tube is good for just .86 mach for compression loads...

I work in an industrial facility and I am trying to come up with a way to measure the strength of X-rays and the danger they pose to the operators of a piece of equipment we have. As of now there is an aluminum enclosure around the part of the machine where the X-rays are emitted, but we are...

I've heard from many sources that chimpanzees are 5x stronger than humans. Yet, they weigh less than humans and certainly don't look "big" and muscular. So the question is, how are they 5x stronger? Do they have muscles that are 5x bigger? It doesn't look like it. Are their muscles more...

Homework Statement An electron is launched at a α=38.5° angle and speed of 4.12×10^6 m/s from the positive plate of the parallel plate capacitor shown. If the electron lands d=3.03 cm away, what is the electric field strength inside the capacitor? Homework Equations t = d/v v0y =...

My industry (tubular steel poles) standardly uses A572, Gr65 and A871, Gr65 for shaft design with the designs taken to the minimum ASTM defined Yield and using loading factors in the design. The A572 specification has for years listed all grades as "Yield Point". The A871 specificaion (which...

In Rc Stephen's book Strength op materials, the longitudinal stress in a cylinder(see) attachment caputure.jpeg. My question is how is the area(pi X d X t ) is derived as my calculations show that this area should equate to (pi x d x t + t x t)

I saw a MIT course on YouTube where the well know professor say that if I augment the height per 10 the strength augment by 100 (square) but the mass by 1000 (cube) so an animal would be 10 time relatively weaker if 10 time taller so he explain there is a limit to animal size because of this. He...

Science quiz question: How to determine the correlation between a car’s horsepower / torque and the maximum break strength of a cable that will hold the motor stationery. Assuming that the wheels of a car do not spin, how can I determine what the required cable’s break strength needs to be...

Homework Statement A coaxial cable has an inner core diameter 6mm and inner diameter of the outer sheath is 20mm. There are two layers of insulation between the conductors, the inner layer from a radius of 3mm to 9mm has relative permittivity of 8 while the outer layer from radius 9mm to...

Hi, why does fracture toughness decrease when a material increases in strength? How do one explain this relationship? Does it have to do with stress vs. strain curve? Thanks.

How are the numerical values of gravitational field strength and acceleration due to gravity on Mars related?

My understanding of colour so far is that if we had, say, a baryon with quark content uuu, we would need to invoke a new quantum number that would allow each quark not to be in the same quantum state to avoid violating the Pauli principle. Now apparently this new quantum number is called colour...

I have read a number of journal article that state that magnetic field strength diminishes inversely proportional to the square of the distance. BUT more than one has stated that the field strength is inversely proportional to the cube of the distance from the surface of the magnet. Which one...

Homework Statement A small engine flywheel rotates at 2000rpm and has 4 permanent magnents pressed into the flywheel at a radius of 10cm spaced 90deg apart 1.2cm diameter magnets. A 1.2cm diameter pickup coil with 500 turns is at the edge of the flywheel. Max voltage detected is .76 volts...

What are the magnitude and direction of the electric field strength at point Z in the following: Point X, q1 = -2.0 x 10^-5 and it is 60 cm to the left of point Y, q2 = 8.0 x 10^-6, which is 30 cm to the left of Z. Essentially, this is what it looks like: X-------Y--Z

Homework Statement 1. Prove the equations. 2.Two solid circular shafts are connected by 5cm and 25cm-pitch-diameter gears as shown in Figure 1.2 below. The shafts are assumed to be supported by bearing, as such bending is negligible. Find the angular rotation at end D with respect to end A...

As a homework question, it asks, "...if the Earth were rotating so fast that the objects at the equator were apparently weightless?" Somewhere, someone said that, quote: In order for the rotation of the Earth to cancel weight, the gravitational field strength should equal the centripetal...

Hi, Does anyone know which insulator will have very high dielectric strength at room temperature? The dielectric strength is the electric filed strength of a material can resist before it breakdown.

One the practice problems i was doing in preparation for my exam was to rank the following nucleophiles in the order of decreasing reactivity, best nucleophile first. Nucleophiles: CH3OH, Br-, NH3, F-, CH3S- The answer was CH3S->Br->NH3>F->CH3OH What I don't understand is why CH3S- is...

Homework Statement A quadrupole doublet, otherwise known as a FODO cell, is made of two thin quads f1 = -f2 = 5m, and the distance between the magnets is, d = 1m. The length of both of the quadrupoles is 0.2m, and I have to calculate their field strengths. Homework Equations Field...

Dear physicists, I am desperate. I am using a QM code to propagate a wavefunction of a system that experienced an electric field pulse. However, in literature all values for the electric field strength are given in V/m but the program asks for W/cm^2! I am kind of very confused here and did not...

Hi. After i first heard about graphene, a few ideas started forming in my head. but before i can even tell if they would work or not, I need some information on graphene i can't seem to find anywhere else. For one thing its molar mass and another, its physical strength.

Homework Statement coils rotating in a magnetic field are often used to measure unknown magnetic fields. As an example, consider a coil of diameter 2.00 cm with 72.0 turns that is rotated about an axis perpendicular to the field at a rate of 20.0 Hz. If the maximum induced emf in the coil is...

I'm building a giant set of monkey bars for a gym and I'm curious about the strength of material I plan to use.I'm going to use two 4x4 3/16 thick steel tubing that will run 20 feet long and sit on top of the same material at each end 9 feet high.I will brace the top corners at each end. I'm...

I am looking into calculating the weld bead strength. I am unsure of calculating the shear stress..the attachment has a drawing..any help is appreciated

Homework Statement So basically we're given a capacitor, or 2 metal plates, which has the capacity of 400 pikofarads (4*10^-10 F), a voltage of 200 V, and the distance between the two plates is 2 mm (2*10^-3 m). a) Find the charge of a plate. b) The strength of the electric field. c)...

I think this belongs here because its about magnets, except for the adhesive part which may be materials. Im improving my refrigerator door magnets that constantly get knocked off or shift around all the time. 1. What thickness of neodymium magnet will saturate a refrigerator door?? For...

2-D Kinematics Riverboat problem, finding current strength?? Homework Statement A boat whose spead is 2.20 m/s in still water must cross a 260m river and arrive at a point 110m upstream from where it starts. The boat's pilot has a heading of 45 degrees upstream, what is the current speed...

Homework Statement Write an expression for the gravitational field strength E at a point distance r from a planet of mass M. (In my diagram, there are two planets with mass, m and distance 2a apart) Homework Equations The Attempt at a Solution The resultant gravitational field...

Hi all, I've got a pressure vessel that is just an aluminum cylinder with flat caps welded to the ends. Currently, I doing some FEA to properly size those flat caps for a certain factor of safety. Since the pressure in the tank will cause a uniformly distributed load on the wetted surface of...

Homework Statement There is a charge of -4.05mC at (3,0)m and a charge of +3.85mC at (10,0)m. And I have to find the strength and direction of the field at (2.5,7)m. (Direction to be in degrees). Homework Equations E=(kq)/r^2 The Attempt at a Solution I've found the fields to...

Hi all I am looking to measure minute changes in electric field strength. I found this article http://www.physorg.com/news74876394.html" which describes how scientists at harvard isolated a single electron in a highly evacuated, absolute zero chilled chamber and manipulated its movement using...

Hey guys, I have searched for information, but I'm looking for an explanation on the difference between a safety factor and a service factor for gearing, and how you would use the latter of the two in calculation (i.e. does it work like a safety factor?). Does anyone have any references that...

Homework Statement The bars in the truss each have a cross sectional area of 1.2in^2. If the maximum axial stress in any bar is not to exceed 25ksi, determine the maximum magnitude of P of the loads that can be applied to the truss. Determine the elongation of each member. E=29,000 ksi...

I'v got an interesting querstion to ask. Hopefully someone who's good in the fields of biology will reply. Most people often picture a person as big and bulky when they say he's strong. I always believed that size doesn't have to do anything with strength (take a look at powerlifters)...

Hi, I am trying to work out the electric field strength associated with a number of different electronic systems at a given distance. I am able to simplify the systems so that I only need worry about the fields from a high-voltage busbar or cable. I know that electric field strength from a...

okay guys, i think I am out of my depth on this problem. Im doing a long investigation on eddy currents, and i derived a formula. I am reaching the end of the investigation, and so i wanted to compare my experimental data to expected data. One of the factors i was investigating is the...

I have to spec a sensor to monitor the magnetic field of a DC solenoid element. The specification for the solenoid includes its length, DC resistance, current at the applied supply voltage, and most importantly, the expected Dipole Moment of the unit, as 42 Am^2. I plan to attach a solid...

Hi all, this will be my first physics qns:D more to come... I just learned that value of g at the equator is not exactly equal to the gravitational field strength. Can anyone explain with workings? i don't really understand my teacher workings. Also can i clarify if -We're assuming Earth...

Homework Statement Just wondering if I were to plot the magnetic field strength as a function of time of an RC circuit if they would be related through the time constant in the current (I = Ioe^-t/RC)?

Does anyone have access to a chart shown surface finish vs. impact of fatigue strength at 10^6 for various matals? In our company we limit the surface finishes to 63 Ra max for highly stressed areas. But where did that value come from? The best way to find out is to see a chart showing the...

Say we can set the strength of the strong force weaker, can the glouns then range further and further from a quark? Can we eventually get the strong force to look like the electromagnetic force as far as the range of the force is concerned? Thanks for any help!

I have an "odd" use for pvc pipe. My house is made exclusively of styrofoam and plastic. (and a geodome to boot) I need to stick with this as any other material that was used has failed miserably (wood and steel mainly) my question is, how much weight can a 10' piece of 3" schedule 40...

Sick of watching these documentaries that don't even remotely explain some things in detail. Like... How is bone almost as strong as steel? Some thin steel rods lying around my house are very hard to bend slightly, but my stainless steel scissors in the vice can take a mild hit from a flat...

Hey, I'm 18 (well, in two months) and I have the hypermobility type of Ehlers-Danlos Syndrome (in short, too elastic collagen). Recently, I've started strength- and cardiovascular training to improve my musculature in order to compensate for my weak tissue. Since it's a reasonably rare...

Why does clear tape (used to tape up cardboard boxes) become increasingly harder to tear along the axis that it is stretched? It seems that after a certain amount of deformation, it becomes nearly impossible to tear. This seems to be different then just the restoring force (as opposed to...