Shock Definition and 238 Threads

if i touch the live (single phase) wire , i will get a shock.But current will have to flow through the body , via the floor , walls of the building , and into the Earth . But cement has electric resistance higher than 1gigaohm so rms current = 220 v / impedance impedance > 1 giga ohm so rms...

My son occasionally pulls plugs from powerpoints. We tried to get a powerpoint cover but the strong tape here in Japan is weak and it fell off easily. I was just wondering how much electric shock he might get from pulling out the cord when the device (a fan) is operating. Its a two prong...

I am shocked after reading this: http://googology.wikia.com/wiki/Finite_promise_games So, let's take strong Goodstein function. It is total, but this fact is unprovable in Peano Arithmetics. No problem, I just understand that PA is too weak. Goodstein function is total, just take stronger...

Below is a 2 part question regarding gravitational pipe flow, I have managed to do Q1) and have got an answer of 144 kg/s. However Q2 asks that shock losses be considered, Although I know how to calculate the shock pressure loss I am unsure of how to apply this to my calculation to get a new...

I stumbled upon this concept when studying gas dynamics. What I get from my readings it must occur when Mach number is really close to 1. But I didn't understand how the property relations across a shock wave is affected by it.

Evening all, I've recently undertaken a project where my roll is to analyse the suspension of a mountain bike. The suspension unit in question is a Rock Shox Monarch RT3. To give a brief summary: The shock uses compressed air as the spring, the pressure is adjustable via an air valve. The shock...

Homework Statement Hi everyone! I'm still trying to make my way through the wonderful land of oscillations. That's going to take a while. :DD The springs and shock absorbers of a small truck have been conceived, so that the truck body sinks of a distance s = 100mm by full load (total mass m =...

Say there were to be two normal shock waves that were moving towards each other at different speeds. What would happen when they collide with each other? Would the shock waves flow past each other or would they be reflected back from the direction they came from? Also how would you be able to...

Am not sure if I've posted in the right section but I couldn't find anything relevant to Waves in Supersonic Flow, so apologise in advance! Post is a little long but I will appreciate any help! Academically am not very gifted and also have a mathematics disability so I tend to question even the...

Today I was over at my wife's parent's house. My wife and her mom were doing a puzzle on a work bench. My wife told me she heard a buzzing under the work bench. Her mom has hearing problems and couldn't hear it but I certainly could, it was quite loud. I looked and it was coming from a lamp type...

How would one calculate the speed of a shock wave or intensity? For example, let's say something with a mass of 10 kg, with a velocity of 1000 m/s, travling in a straight line ,in Earth's atmosphere, at sea level . what formulas would one use to figure this out? Thanks in advanced

I am living in an apartment and suddenly we started to get an electric shock, at random, when touching a water tap. Since I am an Electrical Technician, I started my research on the origin of the problem, and after carrying out a series of tests I found out 'at the end' that turning off all...

I am doing the Bottle Rocket event for Science Olympiad and I have to have an egg strapped to an air pressured rocket which should not crack on the way down. What is the best and lightest material I can use to absorb the impact? I was thinking of a sponge or cotton. The rocket will be floating...

I understand that electrically charged objects such as a rubber balloon or even the human body can hold several thousands of volts. What's troubling me is that I know the current that results from an electrostatic discharge is not enough to cause serious damage or kill a human, yet if you touch...

A jet flying directly over you at an altitude of 3300 m produces a shock wave. The angle of the shock wave is 43 degrees. How long will it be until the sonic boom reaches you? How far does the jet travel during this time interval? I know that I can figure out the second part of this problem if...

Electricity travels from higher potential to lower potential then why don't we get an electric shock while holding aa high potential wire without touching the Earth ( we are also at lower potential)

So I was sitting around pondering about forces, and I found myself thinking about shock-waves. Whether they're caused by supersonic travel, or explosions, the pressure at the front of the wave-bow shock pressure is a force. So I started thinking of a way to generate them without having to go...

Shock wave is caused by the disturbance of air by the airplane. When it propagate the mechanism should be the same as that of longitudinal sound wave. Why sometimes it can travel faster than sound? (also see: http://physics.info/shock/ )

Greetings, in my total distraction of designing the ultimate Off-road/Overland vehicle, I've been thinking about the following matter: Is it possible that a vehicle can be raised/lowered by pumping/removing extra oil into the shock absorber? And if so, would it affect the ride? Could it be...

Hi I want to ask which of the cast steels or forged steels provide with better shock absorption? The component has to be used in the under chassis of heavy trucks in bumpy roads. Can anyone help me with that? Thank You

It is said that with dry hands, you can touch the poles of a car battery and it will not shock you. I understand this is because dry hands have a very high resistance. Now if you have wet hands, or even worse if you have needles stuck into your skin that are attached to the battery posts, this...

Hi all, I have some prob to undestand the shock wave in compressible flow, more precisely the "theta, beta, Mach curve) - Why when "theta" exceeds theta (max) there is no oblique shock? (how we can explain this physicaly)? - What is the difference betwwen weak shock and strong shock? - why in...

I was wondering, is it possible to charge oneself with static to an extent that would be lethal or even damaging to a significant extent beyond the usual discomfort? What are the governing calculations? Instead of the usual carpets would any other materials in an exceedingly dry climate give...

Is there an equation to calculate the oblique shock angle for supersonic flow when the given angle of attack is greater than 0, but less than the half angle? In my particular practical experiment, the half angle of the aerofoil is 5 degrees, so want to get a variety of figures between 5 and -5...

Gruxg has posted a thread on November 4, 2012, titled as "If you touch a live wire without touching the ground, do you get an electric shock?". I think that this thread would deserve more consideration as it discusses an essential subject but unfortunately it is closed for further replies, so I...

Can anyone explain the use of capacitor in a shock pen

Greetings Recently I read that radio jets from Quasars and Radio Galacies exhibit a behavior similar to shock diamonds which reopened a creaky old door in my mind because i first started reading about Shock Diamonds as a child of about 8 which may be part of my difficulties in understanding this...

Hello everyone... Help me out.. I installed a geyser 3 weeks back which has a rating of 15A and I connected it to a 32A MCB. This is connected to a 16A separate MCB in the main board. Whenever I turn on the geyser, it works for some 10mins and then turns off without water getting heated. I...

Hi, I've got a question which I can't google, I' haven't found anything about this. My dog simply shock me. Yes, I know static electricity and stuff but I wonder why this happens only when he is excited about something? For example I tell him that we're going for a walk and when I touch him he...

If I have 2 shock waves propagating at different speeds in a tube, let's say to the right. Let's say initially one of the shocks (shock 1) is ahead of the other (shock 2), but shock 2 is faster than shock 1, so eventually shock 2 will catch up to #1. What happens when they catch up? Do they...

If I built up static in me and then touch a doorknob and get shocked, am I then sufficiently grounded to be able to touch electrical components? Or was it just that the extra electrons were discharged and I should still ground myself in another way before touching electrical components?

I have been asked to determine the "shock regime" of a oblique shock / bow shock interaction based on the angle of the impinging shock and flow conditions. What does this mean? My initial thoughts were that I was being asked to determine whether the shock was strong or weak, but since the...

Homework Statement Total temperature of mixture= 600 K, mass fraction of vapour to mass of total mixture=0.01 Homework Equations Ideal gas law, Mach area relations, Rankine-hugoniot equations The Attempt at a Solution Applied Clausis-Clapeyron relation to find vapour pressure, Then found...

How does bombs produce shock wave and blast waves. ...

Is momentum conserved? I am considering the Euler equations in conservative form and solving the Sod shock tube problem I have written a Godunov finite volume type solver. It solves for density ρ, momentum ρu, and total energy E; therefore, I would expect all of these quantities to be...

Assuming a 2 pin connector for an SMPS power supply, what is the role of the R and C that are connected to Case ground. Usually R is in Megaohms and C around 0.1uF,2KV. IS there a risk of shock when the case is touched?

The current of a regenerative shock absorber is modeled by I = -5e^(-0.5t) cos t - 10e^(-0.5t) sin t Given that the charge, q, in an electrical current is related to, I by I = dq/dt and that at t = 0 the charge of the regenerative shock absorber is q=80, find the charge when t = 5 Hint=...

Which is the problem when a human being is electrocuted: the high voltage and/or the high current? What the high voltage make in the body human (such as brain, heart and other organs)? What the high current make in the body human (such as brain, heart and other organs)?

Hi all, First to clarify: this is no homework question. I am working on a construction and am really puzzled about the following problem. I need a spring to hold an object in place during sideway shocks. I am really puzzled about the fact if friction helps one or two times. In other...

Hello, I am wondering, on a Normal Shock Table, what are the two most right columns supposed to mean? What is the ratio P02/P01 and P1/P02 supposed to be?

Homework Statement How much energy must the shock absorbers of a 1240 kg car dissipate in order to damp a bounce that initially has a velocity of 0.840 m/s at the equilibrium position? Assume the car returns to its original vertical position. Homework Equations Fs = -kx The spring...

When the powerful (nuclear) bomb explodes it generates the shock wave that destroys everything around it. I want to know, does the force of this shock wave depend on the air pressure and density? Imagine that we have got powerful (nuclear) bomb and the object (rocket in this case) that is...

Homework Statement A shock wave moves away from the center of the explosion, its pressure is decreasing, and its speed tends to a constant value. In the filming of a particular explosion, the following data was obtained: t(s): 0, 0.02, 0.04, 0.06 ,0.08, 0.1, 0.12, 0.14, 0.16, 0.18...

There was a recent thread (now closed) where I claimed that a body accelerating beyond the speed of sound emits a shock wave that propagates spherically backward in the rear hemisphere. I have reviewed literature on fluid dynamics and it is quite clear to me now that I was wrong. There is no...

what exactly speed point does shock wave will start to appears..

I need to understand how much kinetic energy a particle can absorb which initially is at rest and suddently is exposed to a shock wave. Detonation velocities are very high, on the order of 6000 m/s, but I assume this is the velocity of the shock front and not of the gas molecules themself...

Yep, half light speed or thereabouts; superhero story :). I'm writing a story about this fellow who gets super powers, including super speed. He can move, fly, at up to 100 000 miles per second. He can also move around at normal speed if he concentrates on what he's doing. Right after he...

For example a phone in a case is dropped, would it suffer more in a plastic case or a rubber case? Thanks

Hi, I`ve had past experiences with pressure switches giving "strange" (pulsed) signals due to nearby discharge valves closing or opening. Looking a little into it I run into reading about compressibility theory and "shock tubes". Just for info, a "shock tube" is a tube with 2 zones...

nitrogen gas is said to prevent cavitation in shock absorbers and thus provide a comfortable ride.. i want to know what actually happens in a shock absorber when nitogen gas is used. how does it prevent cavitation?