Crack Definition and 56 Threads

For quasi-brittle materials, there is an energetic size effect as well as a statistical size effect, as described here. However, it seems to require a stress gradient for it to play a role, as in the example given with a 3-point bending test. The stress at the middle of the fracture process...

Say I have a rod with a notch at the very centre and another ro with a notch at the very end. Both rods are identical in length radius materials etc. Who would be impacted by the notch more? And if then both were to support a load at the end of the rod (both in tension), what effects would the...

I'm using the wikipedia page on Size Effect to get an understanding of it. It identifies Statistical and Energetic size effects and two types within energetic. I believe I understand statistical, as it seems to essentially say that assuming there's some variation in the material strength, the...

If i have a thermal shock in a thermo-elastic material with crack mode I propagated ? what are the stress-strain relations in this case? or what is the factor K relation? "sorry if the question is not true, but i hope you understood what i mean"

Are there any conditions under which glass cracks spontaneously? Just now, my mother's rear windshield cracked spontaneously. The story according to her: Slowly approaching a stop sign. No busy traffic. No trees/animals in sight. Few people. Suddenly, the rear windshield cracked with a loud boom...

My question here is regarding fracture of materials. I have problems in understanding some concepts. Now, for static loading, there is a property called KIC (fracture toughness). By equating our stress from the static load to this KIC, we get the maximum length of the crack which does not...

Hi, Please consider the problem below of a central through crack with a concentrated load as shown below. Can someone please help where does one come across such a problem in a practical world? How will I have a concentrated load opening the crack? In the physical world, what is that...

Nice little puzzle: http://www.bbc.co.uk/programmes/articles/5m5cv4NM5dWx108YgCQXj9J/can-you-crack-gchqs-code-breaker-challenge I didn't find it particularly difficult (less than a minute to spot how to do it, and a few minutes to actually work through it), although Google translate thinks the...

I got a freeware encryption software with only 128 bit. How fast it is for hackers to crack 128 bit file encryption?

I have had a number of TVs - both CRT and flat-screen - that make a loud crack occasionally. It does sound just like appliance settling from heat expansion/contraction, but I'm not so sure that's what it is. It cracks exactly once and only once, and does not seem to be correlated with heating...

I'm 17 years old, I´m mexican and I like physics

Hi guys, My name is Rogelio H. Aguirre, a grad student from the University of Waterloo working on MEMS sensors. Currently, I am working with micro laser welding suppliers to fabricate the packaging of a pressure and a temperature sensor. I have some experience on weldings, but not in micro...

I'm working on a project for a bottling plant that is trying to make a vision-based machine to detect cracked glass bottles before they attempt to fill them. It seems that the vision & backlight approach is the standard way to do this in the industry, but the shape of the bottle in this...

The encryption method is extremely simple and the first letter is already in plaintext (the character number that is). The plaintext is plain english. [79, 32, 79, 39, 45, 39, 112, 21, 50, 64, 37, 5, 107, 4, 36, 87, 35, 81, 48, 94, 57, 92, 46, 93, 125, 9, 102, 70, 42, 69, 51, 86, 92, 5, 106...

I need some information urgently. I am working on crack of a 2-D cantilever beam. One side of the beam is fixed. I am applying a sinusoidal time varying load on other end in Y-direction.Beam length and width are 100cm and 10cm respectively. crack is 05 cm in y-direction. I have attached data and...

If I took a hammer to each of the screens, which would crack first with a minimum amount of force? If I put a screen protector on it, would it change the answer of which one would crack first? I tried to pick two models which had similar frames. If the using different models actually makes it a...

Is it harder to crack a smaller screen or a larger screen? Why? For example, if I hit an iPhone with a hammer, would it break more or less than if I did the same to an iPad? Would it change which is more safe if I put a screen protector on? The force would be the same in both cases but it...

Homework Statement Here is the issue I met.Could you refer to attached file? 1.We glued one piece aluminum block and one piece copper tungsten block on substrate. The aluminum and copper tungsten block have different height.The glue thickness underneath them is different...

How long to crack this encryption method by brute-force ? I have a 64 character password created using a simple substitution cypher of the base 64 character set, i.e. all characters are included in the password , none are repeated. How long would it take a modern computer to crack this...

Anyone want to take a crack at deciphering my prof's handwriting? http://i.imgur.com/8rDPmxK.jpg There is a question mark and closing bracket at the end that was cut off FYI. Sorry for the large image. Not sure how to make it smaller.

A few weeks ago I accidentally dropped my droid on some concrete :) Impact location was near the top center, slightly offset. I notice that an initial crack propagated downward about 1 in before making a perpendicular split. Each side of the crack continued along the phone glass heading towards...

I was wondering if anyone has ever tried to model/fit a crack on a material surface with a Weierstrass function.

please help i have to write a MATLAB code for DETECTION OF THE LOCATION AND SIZE OF A CRACK IN STEPPED CANTILEVER BEAMS BASED ON MEASUREMENTS OF NATURAL FREQUENCIES the reference paper is DETECTION OF THE LOCATION AND SIZE OF A CRACK IN STEPPED CANTILEVER BEAMS BASED ON MEASUREMENTS OF...

Hey guys, I'm new here so please be easy on me if I break any "unwritten" rules. I'm doing a design study on brittle crack growth in ductile materials. As I understand it, when a macroscopic crack is found in a load bearing plate, holes can be drilled at each end to reduce the internal...

Homework Statement Create a multithreaded program (Java) that finds a word in a text file and reports the lines one which the word appeared. Word lines should be reported in the order in which they appear. Homework Equations The Attempt at a Solution I know that I can just...

If you had a bowling ball sitting statically on top of a perfect rectangluar porcelain tooth, and the bowling ball caused a crack in the porcelain tooth (hairline fracture), but then you immediately took the bowling ball off the tooth... wouldn't there be no work done since the bowling ball...

http://www.canyoucrackit.co.uk/index.asp If you can crack it, you will get a job as a European Spy! That's the link to where you can attempt to crack the code. You get unlimited attempts! P.S. If anyone gets the code, please feel free to post here, lol

Help needed with crack growth simulation in Ansys implementing CZM Hello, everyone! Could you, please, help me with the following issue? I’m trying to simulate a crack growth in an anisotropic media using cohesive zone model (CZM), and the results I get do not agree with my expectations...

http://www.nature.com/news/2010/100707/full/news.2010.337.html Apparently the proton is about 4% smaller than thought, which is somewhat challenging for QED. It could be new effects or experimental error of some sort. Any such guessing is speculative at this time, but what would you think?

Could you crack a whip while moving faster than the speed of sound?

Vacuum Physics? I would like some clarity on a problem I think is attributed to a vacuum space. This is what happened...I have a small room that is 7' x 10', there are two metal doors directly across from each other on opposites sides of the room. It seems that when I want to close the door...

Why are personal and "crack" theories not allowed? I always wondered about this rule. This is a skeptics section of the forum and if you have something to say, well wouldn't it be reasonable to question it and take it apart than to rather disown it? I asked a question earlier about Forces by...

my friend and i are doing our science fair experiment on the strength of eggshells. we plan on using a pendulum to crack the eggs but do not know how to calculate the force of the pendulum, which we can then use to find the strength of the eggshell.

In Solid Mechanics, what is 'crack nucleation'?? and how does this relate to fatigue and creep loading? thanks

Hi I have a question I need help with. Im trying to find out how much forces that a pouch (balloon) creates on the inside walls when it hits the floor after a fall. A pouch (balloon) with one litre of water falls from 1 meter down to the floor. How much force must the "walls" stand...

9 30 20 39 59 50 79 73 88 95 104 131 132 135 144 150 166 185 198 190 218 215 232 235 241 269 265 270 300 305 313 325 338 348 355 373 I will not be posting the algorithm used to generate this coded message. Good Luck!

I am trying to determine the critical crack length of a part using finite element analysis. The software I am using (ABAQUS) has the ability to perform fracture analysis. I model the part, create a crack, and ABAQUS will output the stress intensity factors (modes I, II, and III) and contour...

like if I was to say "this beam can take this much load" does that mean if you put any more load on it, it will crack? Sorry if this is a confusing question, help my understanding if you can.

I am thinking about the following situation. In a stagnation water loop, the pressure is building up. A crack occurs due to the expansion of the water. What will be the solution approach to determine the flow rate of the leakage? Please give some hints or references. Thank you.

Hello, We have an installation in which we will be placing a 1/4" thick mirror which spans 7ft across and 5ft in height directly next to a "line of fire" (a gas pipe with holes which will have a flame approximately 6" in height). Our concern is that when the line of fire is turned on in...

lol if you have time for a 6minute video watch this homeless guy is talking about suposed non-linear algebra. I couldn't follow ... http://youtube.com/watch?v=Tc-kjz9s2IA&mode=related&search= If anyone can follow this to me the numbers just don't seem to add up please explain...

|1|4|6|9| |D|-|-|-| |S|K|J|A| |Y|U|J|-| |S|G|B|-| |Q|F|J|A| |L|H|U|-| i would love to see anyone break this one i found it on a nothere site that said you could give it away but it took me 5 computer programs that crack encrypted text like that and a few books took me for ever.

I feel justified in making a reusable thread because it is unique to this section. Here's my idea. I take a few sentences or words that make sense and apply simple coding techniques and if anyone cracks it, I move onto the next one. I will not be posting any hints and will not move onto the next...

Math Teaser! Can you solve this? [tex] \frac{4 \infty}{\sqrt{-1}} {(1+\sqrt{-1})^(1/\infty)-(1-\sqrt{-1})^(1/\infty)} [\tex] Edit: why this latex is not being generated? Anyway the "expression" is [(4*inf)/sqrt(-1)] * { [1+sqrt(-1)]^(1/inf) - [1-sqrt(-1)]^(1/inf) } where inf stands...

There's a funny flash game where one of the puzzles is to guess a four-digit password with digits from 1 to 8. After each guess, the puzzle gives you some number of x's and some number of o's, with the x's indicating how many numbers you guessed correctly and in the right place, and the o's...

Is my Kasamba.com "expert" on crack? This question is not for school, it's something I'm doing on my own. About a year ago I was told on this board that in theory Mass has no effect on the top speed of an aircraft. Drag opposes thrust, Mass (weight) opposes Lift. Mass may slow down the...

a number puzzle... tell me a the lowest number for which the number just below it is divisible by 2 ,the one below that 3, below that 4 ,and below that 5 ,and below that 6 .

http://www.msnbc.msn.com/id/7822879/

So I'm going back to Mexico tomorrow (today). I thought I was going back at 6:00 tomorrow afternoon, but found out late yesterday that I'd be leaving at 6:00 in the morning. Fabulous. So I decided that rather than get 3 hours or so of sleep I'd take a nap in the afternoon, drink a little, and...

http://www.ldolphin.org/energetic.html looks like it to me but i would like other people's opinion.