Impact Definition and 992 Threads

Hello Folks! I want to find the maximum applicable force on a full suspension mountain bike and i will use this force on a FEA software structural analysis for a uni design project. This bike has a rear suspension with 400 lbs/in spring rate.Also rear wheel vertical displacement(travel amount)...

by Ken Croswell The Martian moons look like asteroids—dark, crater-pocked, and potato-shaped—suggesting Mars had snatched them from the nearby asteroid belt. But now planetary scientists have conducted the first computer simulations that bolster a controversial alternative idea: The satellites...

Homework Statement Two elastic bars are joined. A step wave is coming in from left. Derive the shape and magnitude of the reflected wave if the right bar is approximated by a rigid body (point- mass) that is free to move in the axial direction. The Attempt at a Solution I have problem with...

Homework Statement A bullet of mass 2.0 * 10-3 kg is fired horizontally into a free-standing block of wood of mass 4.98 * 10-1 kg, which it knocks forward with an initial speed of 1.2 m s-1. (a) Estimate the speed of the bullet. (b) How much kinetic energy is lost in the impact? (c) What...

I know an exact answer is impossible but an estimate will prove the following statement impossible. Allstates insured driver said he backed up hit my sons motorcycle, did not feel the impact, and stopped when he heard it hit the ground. He parked and got out and the motorcycle was 3' from the...

Homework Statement I have always learned (and read) that an increase in the number of bits causes the height of the 'step' on the graph to decrease. I tried to think about it but cannot come up with a proper explanation for this. THe books I read do not explain why? Can someone please explain...

In the Earth forum, there is a thread about the Nepal earthquakes which started with a mag 7.8 earthquake. This thread is about the human impact. More than 2,200 confirmed dead in Nepal earthquake http://news.yahoo.com/aid-starts-coming-nepal-quake-kills-nearly-2-050207892.html International...

Hi, I've got this water circulation system. Diagram attached: http://postimg.org/image/wmf2hql6p/ In the upper container jets of water come out from the pipe due to the small holes I have drilled into the sides. I would like to know how I can work out the impact pressure on surfaces that may...

I have performed an impact test on different football shin guards to assess their performance. I am however confused with the readings measured by the accelerometer I have used. The sensor was attached to a striking mass of 4.3 kg which was dropped at different heights. The graph I have attached...

Hello, I just have a quick question about electron impact ionization. How exactly are the electrons accelerated? Are they attracted by an anode?

I have an old Windows Vista PC that has started acting up. Normally it is in the sleep mode. Lately when I push the start button the fans start running for 2-3 seconds and then it shuts down. This can happen many times in a row but if I lift one side of the computer case a bit (which lies flat...

Hi, I'm just an average guy here, mostly self educated, and am looking for experts to verify my theories on developing revolutionary impact protection. If I disrupt direct impact to the head using a highly elastic layer of material, does that create an inelastic impact interruption? A helmet...

Hi, I am dropping an object of mass m at different heights on another body. From the accelerometer I have I can get the g-force and then convert it into Newtons. What I am wondering, is the force converted into Newtons equal to the impact force the mass exerts on the body?

Homework Statement I want to find the ionization cross section in a mass spectrometer for the gas Argon. The value obtained should be in the 2x10-16 cm2 range. Homework Equations Q = ionization cross section I = K(V,B)xNxQxdxIe Where I = (0.17 x 10-11, K(V,B) =1, d = 0.1 cm, and Ie = 5 x...

Hi. I just saw this: http://phys.org/news/2015-03-einstein-scientists-spacetime-foam.html They are saying that they have found data showing that the "quantum foam" does not exist. What is the impact of the disproof of "quantum foam", anyways, on the search for a theory of quantum gravity?

Hi, I am doing a drop impact testing on a football shin guard. I know how to find the impact force but how do I determine the energy absorbed by shin guard during impact?

Is there any way to obtain the exact function of force with respect to time of an impact? I have heard of the equation: http://www.sciweavers.org/upload/Tex2Img_1425867132/render.png which tells you the impulse of an object with constant velocity as it impacts another object.

Impact: Earth! A meteor/comet impact simulator(text only) provided by Purdue University. Lots of fun. :smile: You can smash things into the Earth varying the diameter, density, velocity, angle, land or water entry, and your distance from impact. 1 meter: very boring. happens every 1.1 year...

Homework Statement " A 1100 kg lift is suspended by a series of 24 steel cables of mean diameter 20mm. The cables are attached to the lift top and are arranged so that torsional vibration is minimised.If the cable is manufactured from steel with an elastic modulii of 185GN/m2 and elastic...

Homework Statement The electric field strength is 2.50×104 N/C inside a parallel-plate capacitor with a 1.20 mm spacing. An electron is released from rest at the negative plate. What is the electron's speed when it reaches the positive plate? Homework Equations F = eE = ma vf2 = vi2 + 2ad...

Homework Statement Hello, new to the physics world, I am trying to self-teach through reading textbooks, videos etc and application. I came across a problem I do not know how to begin to answer. A dodgem car of mass 200g is driven due south into a rigid barrier at an initial speed of 5.0...

Homework Statement In this problem, you will estimate the cross section for an earth-asteroid collision. In all that follows, assume that the Earth is fixed in space and that the radius of the asteroid is much less than the radius R of the earth. The mass of the Earth is M_e, and the mass of...

Why did Dark Matter have less of an Impact on the Universe than Dark Energy? Under a different set of universal laws, do you think it would be possible for Dark Matter to have more of an impact than Dark Energy during an alternate big bang to create a infinitely dense point as a universe?

I need to work out the impact energy for three different drop heights. I am really struggling to get my head around it. Am i on the right lines with this? mgh = (1/2) mv2 Please excuse my basic knowledge, I left school 21 years ago with a D in maths, but I am now trying to improve my maths...

for example say I were to roll a magnetic ball down a hill and placed another magnet at the end of the hill, would the magnetic ball hit the magnet with more force than a non magnetic ball. This question is for my science fair, all people answering must be prepared to answer follow-up questions...

There is a thread on plunging into water but it doesn't specify how you land. Consider that a man plunges into the water vertically with his toes pointing downwards, streamlining his body to the maximum possible extent. How can you calculate if the person falling will die or not? Rather how can...

Hi folks, this is a problem I am having in a collage project I am doing. I'm not too sure about my results and keep chasing my tail using the same formulas, e.g. F=ma etc. I think I need to allow for the fact that the force is applied as a collision but I am not sure how or if I need to do it...

Mentors Note: Posts from a duplicate thread have been merged into this one. Hello, please explain the following in detail. I am a learning assistant (LA) at a major university but am stuck explaining a concept to my students. Does mass have an impact on an inclined plane? A cart with wheels or...

When a stellar object falls into the Earth's surface, it creates a crater on the ground. Most of the times, when people refer to these things, they refer to their age and their diameter/radius. My question is mainly about the radius. Is there a dynamical way to solve for the shape and radius of...

Hi, I am attempting to design a plastic scrap grinder. To begin my calculations I need to know the force needed to shear a certain area of plastic. After noticing that by using the shear stress equation would result in a huge, unrealistic force, it came to my mind that the plastic will be cut by...

I need to find the impact force that can be absorbed by these spacers as shown in the image. The spacers are radially distributed over the shell, and they are supposed to dampen any external impact loads to reduce the effective stress inside the inner shell. Since the FEA model is not showing...

Hi :) Here is a true story... I was in my car which weighs 820 Kgs, I for arguments sake weighs 80Kgs and the vehicle has an acceleration of 0-100 Kph in 15sec I was at a stop and went to go around a stationary vehicle in front of me.. I locked the wheel and attempted the pass but instead made...

1. An asteroid is 10r away from the earth, and traveling at a speed of 12 km/s. What is the impact speed of the asteroid when it hits the earth?2. Gravitation problem: U = -Gm[E]m / r ...I think3. I've been looking in my book and online and cannot figure it out, please help!

Homework Statement [/B] Suppose that an asteroid traveling straight toward the centre of the Earth were to collide with our planet at the equator and bury itself just below the surface. What would have to be the mass of this asteroid, in terms of the earth’s mass, for the day to become 28.0%...

How does TPU compare to other thermoplastics in regards to impact strength? How does the impact strength of PU vary depending on its form?

Can someone please explain the significance of resonance levels that forms when electron collides with atoms. How this resonance levels are different from other levels ?

Say you are interviewing for a tenure-track position...you've got a PhD and a postdoc or two under your belt in your field of specialization. Would the specific courses that you took (or did not take) in grad school have a large effect on the hiring decision? Especially if there is a course...

I'm designing a tool that will be driven by an impacting peening gun. The peening gun will be act like a jack hammer with a flat tipped cylindrical anvil. The tool being hit will have a steel insert that will act to transfer the energy from the impacting peening anvil to the tool. I've done...

Earth is changing constantly and there is still so much we don't know about it. Researchers construct a model of impact for El Nino / La Nina events 17 hours ago by https://sciencex.com/authors/bobyirka/ Phys.org) —A small team made up of researchers from the U.S. and Europe has constructed a...

Homework Statement Once a circular path has been obtain for the electrons, how will increasing current to the coils affect that path? Use equation 1 and the fact that e/m is a constant for the electron. Homework Equations e/m = 2V/B^2r^2 The Attempt at a Solution I'm unclear as to how to...

Homework Statement A student stands at the edge of a cliff and throws a stone horizontally over the edge with a speed of 16.0 m/s. The cliff is h= 41.0 m above a flat horizontal beach h=41 g=10m/s vi=0m/s vf2=vi2+2gh vi=28.64 h=vi+vf/2xt 41=28.64/2xt 14.32 t=2.86 28.64x28.64, 16x16 Square...

Homework Statement A ball is thrown toward a cliff of height h with a speed of 28.0 m/s and an angle of 60.0° above horizontal. What is the ball's impact speed Homework Equations Vf=Vi-at Sf=Si+Vit-1/2gt^2 Vy=sintheta Vx=costheta The Attempt at a Solution first find the vertical velocity =...

Homework Statement What would be the effect of calculated value if: a. Jockey weight is in error by 1 g? b. Distance from vane center to pivot point is in error by 1 mm? c. diameter of nozzle 0.1mm different from actual nozzle diameter. Homework EquationsThe Attempt at a Solution as the error...

Hi! I have apparently forgotten way too much college physics, and could really use some help here. I'm trying to calculate the impact force of an instrument (a Schmidt hammer--uses a spring-loaded piston) that produces an impulse against a surface. The instrument registers a rebound value (which...

So I've been becoming pretty obsessed with base jumpers. However its a pretty dangerous sport and as it turns out (surprise) a lot of them die. I was just wondering how much force the human body can survive. Say a 90kg base jumper jumped off of a 900m mountain and their parachute failed to open...

Hello everyone! I happen to read this forum a lot, but I've never posted/became a member since I didn't have a specific question that wasn't already asked before or because I did not feel I had anything relatively original to contribute. So, I have a question to which I cannot seem to find an...

Homework Statement A ball is thrown from a bridge 200 m high with an initial velocity of 34.4 m/s at an angle of 54° above the horizontal. Homework Equations I'm not sure... arctan Vx/Vy = x? I really don't know. The Attempt at a Solution (a) How high above the throwing height does...

The problem comes up as part of a final master's project in FEM analysis. The project consists in calculating the oscillation response of the World Trade Center towers after the plane impacts. The particular problem I'm having trouble is that I need to transform the plane impact of which mass...

I was reading Cengel's thermodynamics and noticed that he uses a thought experiment to show that there is no machine that is more efficient than the Carnot reversible machine. He says that both a reversible machine and an irreversible machine are connected to high and low temperature deposits...

Hello, i am not an expert in physics (i am a computer scientist) but i have a lot of interest in physics, still there are some questions that i can't seem to answer given my limited amount of knowledge in physics (i had only 1 classical mechanics subject in university, although i try to learn a...