Impact Definition and 911 Threads

If a meteor entered the Earth's atmosphere at 11 or so km/sec and impacted the Earth with a direct hit (by impact time it is 4 kg), what would the force of impact be? I only need a rough answer.

I posted earlier about testing a project to simulate a wood 2x4 traveling at 67 mph, I did not really get the answers I was looking for so I am going to try to rephase it. My project needs to withstand the impact of a 15lb wood 2x4 traveling at 67 mph. I want to simulate this test but in a...

I was wondering how much energy it would take to melt a big enough asteroid considered to be dangerous? Is it even possible? If possible, could it be done fast enough before it impacts? If it is completely melted can it then be somehow dispersed so that it turns into smaller chunks that...

"End the R-word" What you do all make of the campaign to end the usage of the word "retard"? I understand their motivation (to prevent emotional damage to those it offends), but I can't help but think another word will just replace it.

What is the crater size for an asteroid impact as a function of the asteroid diameter? Are there any estimated function?

1. How do we know EM radiation is a wave? Also, how do we know that the magnetic wave is exactly orthogonal to the electronic wave? 2. In the into to A Brief History of Time, SH says that wave-particle duality refutes determinism. How is that conclusion made?

The following excerpt is taken from a Swiss Federal Nuclear Safety Inspectorate (HSK) publication[1]: “In the year 1988 a large scale crash test was performed at the US Sandia National Laboratory in which a Phantom military jet with a weight of 19 tons was impacted at a velocity of 774 km/h...

Please be gentle, I'm not a physicist, I'm a podiatrist trying to find the answer to a problem that has been confusing me! I hope you can help. In podiatry we often use foot orthoses in an attempt to alter the magnitude, location and timing of reaction forces at the foot's interface. A...

Homework Statement Suppose an asteroid of mass 3.9e21 kg is nearly at rest outside the solar system, far beyond Pluto. It falls toward the Sun and crashes into the Earth at the equator, coming in at an angle of 30 degrees to the vertical as shown, against the direction of rotation of the...

I have to fix the connection tag to PCB by using pneumatic jig. The material of connection tag is brass.

The angle of impact along with the mass and speed/acceletation have been claimed to be factors responsible for the depth of a crator. How importat a factor is the angle of impact? are the mass and speed/acceleration more important factors? How much influence will the Earth's rotation have on...

I have a simple question for you but a difficult one for me. My bicycle rim manufacturer tells me that the carbon bicycle rim brakes at 900 pounds of pressure. If we have a cyclist of 300 pounds riding at 30 mph and he hits a pot hole for example. What is the amount of pressure/force he...

Not long ago I was arguing with someone on the Internet (where everyone is wrong) about impact of quantum effects on macro scale objects. Imagine ice-hockey table (one with almost no friction) with number of pucks on it. If you'll hit one of them it is safe to say that pucks' paths are very...

Homework Statement A medieval prince trapped in a castle wraps a message around a rock and throws it from the top of the castle wall with an initial velocity of 12 m/s [42 above horizon]. The rock lands just on the far side of the castle's moat, at a level 9.5 m below the initial level...

My book is talking about how collisions can be very different, basically saying how altering the time of contact affects the force. It then gives an example: "Consider a ball of 200g colliding with a hard floor and a trampoline. Before the collision, each ball travels downwards at 10 m/s and...

Homework Statement A 2.0-mm-diameter plastic bead is charged to –1.0 nC. A proton is fired at the bead from far away with a speed of 1.0 x 10^6 m/s, and it collides head-on. What is the impact speed? Homework Equations Conservation of energy: Kf + qVf= Ki + qVi Possibly U elect/ Electric...

Homework Statement A blue whale materializes 11.5 km above an airless planet with an acceleration of gravity of 6.85 m/s2. What is the speed of the whale right before impact? Use the work energy theorem. Homework Equations Work energy theorem : W = the change in k W=kf - ko w=1/2(mvf2)...

I was watching this charpy impact test video clip - I fail to understand 2 things. A) Why do they cool the metal with liquid nitrogen before they test it? It seems wasteful. Set the standard testing temperature to 25 degrees instead. B) What happens to the metal after it gets hit? Does...

Hi, I am doing question A2/15 B2/23 (specifically part (ii)) at the top of page 50 here: http://www.maths.cam.ac.uk/undergrad/pastpapers/2001/Part_2/list_II.pdf I have done everything up to and including showing the impact parameter is given by b=h/E, but I am having trouble doing parts (a)...

I was solving a projectile motion problem and was wondering if, while going downwards, an object's final y velocity can be less than the initial y velocity. If this is true, would this change the time until it hit the ground? The only reason I was thinking about this is because if x/v = t. If...

I've been trying to figure this out for a few days now and I hope someone can help me out...If an object is lifted 1m above the rigid ground and then it is dropped. What would be to force experience (in Newton) by the object if: - You don't know the exact distant or time for the object to come...

I'm trying to design an impact testing rig and i need to use the currently existing chemical explosion rig as one of the solutions alrady existing in my report. But i can't seem to find very much on this, any help would be greatly appreciated. thank you

Homework Statement Why does a car uses more fuel with lesser air in tyres? Homework Equations Work done =F.d The Attempt at a Solution According to me Friction does no work in rolling if the tyre is purely circular. But when tyes are deflated then they are not circular. Due to...

Okay, so I understand that galaxies spin more like a frisbee than the solar system, and that there is evidence for a lot of non-light-emitting mass (such as gravitational lensing) but how would dark matter account for the difference in the spin of galaxies? Gravity still decreases inverse to the...

Homework Statement A pipe end stop fails when subjected to high pressure and flys of the pipe before impacting with a polycarbonate protective screen. The end stop has a mass of 100g and is 12.7mm dia. as is the internal diameter of the pipe. The instantaneous pressure that the end stop fails...

I have noticed that during traumatic events say, car crashes, Although the crash duration is less then a blink of an eye, it feels like takes much longer. I think horizon covered a research of time dilation perception that failed.* Anyway is it possible incredible powers of the crash increase...

Hi all, I am trying to calculate a value for stress in a right angled bracket. this would be simple for me if the load was a static load, it would cause the bracket to bend around a point etc so i can get moments to find its bending stress. however this bracket will be stopping a moving...

I haven't got my grades yet, but I wouldn't be surprised if I'd outright failed one of my January exams and not done particularly well on 2 others. (Took 5 in total) I know the reason this happened, but I won't go into it because its a bit of a story. I also know a typical physics degree of...

Hi, I am trying to calculate the impact force of a rubber weight falling on a rubber surface. I am aware that to calculate impact force, I need to know the amount of deflection after impact. Is there a way to calculate this, using material parameters, rather than experimentally? Thanks in...

Why, in terms of Physics so forces etc... does the diameter of a the splash from a raindrop increase when the height is also increased?:confused: Thanks (:

Homework Statement A mass of 150 KG is dropped onto a pile of mass 1,200 kg from a height of 2.5m and drives it 7cm into the ground. calculate (a) the initial veocity of pile and driving weight immediately after impact, (b) the average resisting force excerted by the ground. Homework...

Is it possible that the chicxulub impact is responsible for the Earth's magnetic pole being tilted 15 degrees off the Earth's axis? If so, at what angle would the impactor have to have struck & based on that and the Earth's current angle can we estimate not only the approximate day of the year...

I am aware that the LHC accelerates subatomic particles to just under the speed of light then smashes them together. However, at the time of collision, would this mean that the combined speed of the impacting particles is almost two times the speed of light? Or are the particles individually...

I'm feeling so frustrated that I typed out a whole detailed write up & it got washed off. Damn it. 1. How does gravity dilate time? I've been trying to get a conceptual answer that is easy to understand, for I have no background in physics whatsoever & am reading up out of interest. Today...

Hi my question is : Moving the body mass was affected in 5 KG force of 20 Newton in a counter direction to the direction of movement if the speed 4 m / s. Calculate the time of the impact of this force is it right? pi= mvi = (5)(9)=40 kg.m|s pf= mvf = (5)(-4)=-20 kg.m|s t = (pf - pi)|f =...

I am constructing a piece of sports equipment that requires me to know the amount of pounds of force the ball impacts on the equipment with the ball weighing 55 grams traveling a maximum of 75 mph a minimum distance of 10 feet or a maximum of 50 feet. the ball is 5.5 inches around when measuring...

Please can anybody explain why Impact testing is carries out @ -20 degree or @ lower temparatures. & what will happen if it is conducted @ higher temp. Please elaborate.

Pretend there are two accelerating masses connected to a massless string with a frictionless pulley between them. How can the frictionless pulley (Rotational inertia and radius given) affect acceleration in any sort of way? Also, why is the net force equal to Acceleration * (Mass of two...

Well I've searched this forum and didnt see this topic before, so I was wondering what the general consensus is on the impact of Godel's theorem (if any) on a possible TOE? I'm still wading through it all so just wanted some other opinions...

Hi all, Doing a project for 1st year special topics physics module in university and we're thinking of doing the project on stars. Just wondering if anyone might know of any good literature on the sublject that we could look into as part of our research. We have until mid January to do the...

Homework Statement For alpha particles of 7.7 MeV, what impact parameter will result in a deflection of 2 degrees for a thin gold foil? Homework Equations impact parameter equation, b=\frac{kq_{\alpha}Q}{m_{\alpha}v^{2}}cot\frac{\theta}{2} The Attempt at a Solution Pretty easy, just plug...

Homework Statement From the given picture, we know: VA before collision VB before collision the radius to the center of mass of each car from the collision point P e the masses of both the mass moment of inertia of both We must find the velocities of the centers of mass of each car...

Okay. Well I'm in high school and I made an account on this forum to see if I can get some insight on an interesting phenomena my teacher showed me. He asked us which way a tennis ball would bounce if he bounced it on the floor at an angle and let it hit the bottom of a table, and gave us...

Homework Statement [PLAIN]http://img87.imageshack.us/img87/9964/impactforceonbike.png A roller is rolling with a constant speed before and after the drop. How do i figure out the impact force exerted on the wheel when it just touch the floor from a height h? Assume, angular velocity...

Homework Statement A 7g bullet moving horizontally at 200 m/s strikes and passes through a 150 g tin can sitting on a post. Just after impact, the can has a horizontal speed of 180 cm/s. What the bullet's speed after leaving the can? ANSWER = 161 m/s Homework Equations 7g = .007 kg 150 g...

Well I'm 25 years old, and am currently in the middle of a major career change, going from consulting to physics. Now for me my age isn't a problem, i feel motivated and am ready to bust my :blushing::blushing::blushing: for this. However, I've been wondering if it could be a problem for...

Homework Statement An 1800kg car traveling north at 35 km/hr collides with an 1100kg car traveling east at 45km/hr. The cars stick together and skid to a stop (a) what is the velocity (speed and direction) of the two cars immediately after the collision? (b) How much kinetic energy is lost...

Homework Statement Consider two less-than-desirable options. In the first you are driving 30 miles/hr and crash head-on into an identical car also going 30 miles/hr. In the second option you are driving 30 mph and crash head-on into a stationary brick wall. In neither case does your car bounce...

If an average adult male fell from a bridge (ex. golden gate) what would be the impact on his body when he hit still water versus water with waves. What is his acceleration, momentum, and his change of momentum when he hits the water With these in mind how does the fall affect his organs...

Hi guys. Which one has more impact toughness: GFRP or Steel??