Impact Definition and 911 Threads

T1 + V1 = T2 + V2 0 + mAgh = 0.5mAV2A1 + 0 40 = (5/32.2)VA2 VA1 = 16.0499 ft/s Edit: Accidentally Used two notations for Kinetic Energy in the "Useful equations" section. Changed it to correctly notate Kinetic and Potential. This notation is used in R.C. Hibbeler Dynamics 14th Ed.

A local ATV (All Terrain Vehicle) trail has some bridges over wetlands. The original supplier of the wood decking did not properly pressure treat the wood, so several of the bridges are being replaced. One bridge had the decking replaced last year. The contractor replacing the other bridges...

I was told to generate these variables (m, C, alpha, wind velocity) normally distributed and compare the random data with the result and then tell, which of the variables has the most impact. Here I am stuck, tried to compare variances, kurtosis and skewness of the data (the original variables...

To find vx vx = dx/t = 3.86 m/1.5 s= 2.573 m/s To find Ek Ek = ½mvx²= ½(79.4)(2.573)²= 262.8 J W = FnetΔd Fnet = 262.8 J/ 3.86 m = 68 N He hits him with a force of 68N

Hi, could you tell me how to calculate approximate value of impact force during Charpy test (pendulum hitting sample) ? The only formulas that can be found in literature for this test are maximum velocity ##v=\sqrt{2gh}## and work done for fracture ##K=mgR(cos \beta - cos \alpha)##. But it...

I feel this is an easy arithmetic, but I can’t figure out how to get it to work out. Let’s say I have an overall metric of sales data that can be broken down by 5 sales reps. In 2016, each rep makes a certain number of phone calls and their success rate is # of sales divided by # of calls...

Hi there, we are developing a small consumer electronics product consisting of a small 4-layer PCB along with a few PDM microphones and BLE chip/ and antenna, as well as a LiPo battery. We are locating a small but pretty strong magnet next to these components in the enclosure. It is an N52...

This study from Johns Hopkins University shows that even if we manage to nuke an asteroid and "destroy" it, it will have a core back, in almost 2 hours. Nuking them was a bad idea before, but now seems worse. More details here...

It is often said that the mechanical properties of metals are mostly due to their free electrons. I'm talking about malleability, ductility and hardness. So, when they suffer a superconductive transition, I expect a drastic change in their mechanical properties, but I haven't found anything on...

I was reading in Sky and Telescope about the Lunar flash during the eclipse last week, and looking at the impact map (2005-2018) I was wondering why there is a 'gap' with no impacts down the middle. It seems rather unlikely that there would be no 'hits' here. Is this an artifact of the limb and...

Hi all, need some help... I was involved in a 3 car accident, mine was the middle car. The car in front came to a hard stop and I was forced to a sudden stop. I believe I came to a complete stop very close to the 1st car. Immediately after, the 3rd car behind hit with great force shunting my car...

Homework Statement There's a bucket, filled about halfway with water. The water itself is completely still. A perfect sphere with mass m and volume v are given. The depth of the water, and the radius of the bucket (which may be considered perfectly cylindrical) are both given. In short, you...

From a heuristic standpoint it makes sense that when a system goes from being periodic to chaotic, the occupied volume of the phase space increases (while not violating liouville theorem). Since the volume of phase space is proportional if not equal to the entropy, shouldn’t entropy always...

Do you have any own idea, on a way to protect the Earth from a possible asteroid impact? (You can not use technologies that are not invented yet, or imaginary. Those that can be invented in the next, let's say, 10 years, are allowed)

Hello This should be simple but for some reason I'm having some trouble with a test we are performing. The end goal is to determine the average force required to damage a section of steel pipe experimentally with an impact tester. We built the tester and know what energy will hit the side of...

If I am observing a pinging beacon free-falling into a neutron star from a distance far enough away that I am in approximately flat spacetime, I think I observe the pings redshifting as the beacon gets deeper into the gravity well, in other words I see the clock of the beacon slowing with...

Hello, A silly question I'm sure, if a projectile moving at 13.59 m/s with a KE = 527.47 J hits an area of 3 cm^2, what is the force transfer to that area and the resultant pressure applied expressed in Pascals? Do I divide the KE by a volume instead of area to Pa?

Let's assume this is hypothetical...and may need to be in a different forum... but I am just looking for advice, maybe I am being too critical or perhaps not critical enough to get the proper inspections and repairs. Assume my 2016 Chevrolet 1500 (2419kg) was struck by a vehicle of mass...

Hello Everyone, I am brand new to this forum and I am currently doing "student research project task" where I need to conduct my own experiment basically. I am currently struggling to find a formula for an impact velocity. I hope there is someone in this forums that could help me. What I...

I have conducted an experiment that measures the velocity of an object that is moving on a flat surface. The object rolls on four fixed caster wheels. The wheels are made of some kind of rigid material. Maybe nylon, maybe hard rubber. The total mass of the object, including the wheels, is...

Please forgive the awkward title. "Supermassive black hole" uses up a lot of the title character limit. Has anyone made a simulation of what would happen if a neutron star impacted a simplified (Schwarzschild) supermassive black hole? I've seen simulations of a neutron star colliding with a...

There's important experiments showing the equivalence of inertial mass and gravitational mass ( the Eotvos experiments), but I couldn't really find many that show the equivalence of mass (or the stress-energy tensor) in other contexts. These are some of the variants of mass I'm interested in...

Interesting article sent out by Digikey just now...

We know that greenhouse gases are the biggest cause of global warming and that the Earth has gotten warmer and warmer over the past few decades. Question: Since not all locales produce greenhouse gases (namely, carbon dioxide) equally, are the effects of global warming distributed more to...

Can someone help me to calculate the approximate impact on the Earth (as in a mining explosion), of 1 ton of dynamite. And also the equivalent impact of say a 1 ton rock dropped from 10 meters. Trying to estimate this for writing purposes, I very roughly got: Impact of 1 ton of dynamite, Work...

As a neophyte when it comes to the relativity solutions I have been surfing the web. I came across something in Science Forums. <speculative link deleted> I have now become interested in what gravity does to light. My understanding of the post above is that the reference frame for light...

Homework Statement Homework Equations impulse = mv The Attempt at a Solution so i found the velocity of the blob of clay now i am trying to find the direction. i took the xcomponent initial stuff which was 0.04kg*4m/s*cos45 - 0.03kg*3m/s Then set it to the final x component stuff which i...

Homework Statement "A jet of water issues from a nozzle, of diameter h_1=0,102 m (and depth b=1 m), at a speed U_1=2,02 m/s. The jet strikes a flat plate of mass M=2,05 kg, as shown in figure, and it breaks into two jets of equal speed and diameter h_2=0,122 m and h_3=0,102 m. Determine the...

Ok, here is a small back story: I love both airsoft and paintball. Airsoft, for those who may not know what it is, is a sport where you shoot 6mm plastic bbs at each other. The bbs have differnt masses to them.. .20g, .25g .28, and .32 are common masses. When i first started last year, i was...

Homework Statement Consider the elevator and screw in Example 2-17. Assume the velocity of the elevator is 16 mls upward when the screw separates from the ceiling. (a) How far does the elevator rise while the screw is falling? How far does the screw fall? . I have only problem second part of...

Hello,I've read somewhere that during launch rapid change of RPM causes an increase in torque?What is the point of this?İs that the reason why cars tend to make tires slip when we try to launch at very high RPM?The extra torque added to engine torque?

So this is my first time posting, but I´ll do my best to be clear (be advised, I have translated the names of the variables from portuguese to inglish so sorry if it is confusing) Today I was asked to solve a physics problem in class, which I had never solved anything else like it before and I...

This is the technical article: https://support.google.com/faqs/answer/7625886 Please do not ask me for an executive summary. I fail Summary 101 repeatedly. Just ask my family. Google fixed the problems and has run extensive tests since September. They found little performance degradation...

Homework Statement (x^2 + y^2)/a^2 + z^2/c^2 = 1 Homework Equations [/B] The Attempt at a Solution the answer is : b(θ) = R / (f^2 * tan^2(θ/2) + 1)^0.5 I can't understand how to calculate this. My attempt : (x^2 + y^2)/a^2 + z^2/c^2 = 1 from this. b^2 + z^2/f^2 = a^2 , f = c/a, z =...

Hi everyone! need to calculate the impact force done by the ladder to the head explained in the drawing. Can anyone help? Kyrre

Hey guys first post on here for me. Graduated with a BS in Civil Engineering and working full time. Have a problem on my desk that myself and many coworkers are trying to figure out and would like some assistance as we haven't done anything like this in years. Not sure if we even have the...

Problem I am designing a force sensing system with piezoelectric force sensors to determine the impact force on an object during a collision. The sensor will be placed between an aluminum block and either a TPU or PLA 3D printed "cover". The cover will be 5cm thick...

Greetings all, I am an undergrad working on my first first-author paper in theoretical / computational condensed matter physics (near the computational materials science end of the spectrum) and I am looking to getting it published. My advisor has published in many journals, from mid to high...

Imagine a moving rigid body B1 like a golf clubhead impacts with a stationary elastic body B2 like a golfball. Imagine that the initial velocity of the golfball at time T1 is zero, and the final velocity of the golf ball at time T2 is some value. Imagine that time T1 is when the clubhead first...

How much more refined are the various variables of the Drake Equation in view of the recent findings by the Kepler Telescope? I imagine fp and ne would surely be better estimates. Is there a study on this anywhere?

Hello, I understand that when we drop an object from a certain height on the floor, there is a force of impact (action reaction) once the object reaches the ground. I can easily calculate the final speed of the dropped object before the impact but I need to know either the time or the...

Homework Statement A parallel-plate capacitor is charged to 4850 V. A proton is fired into the center of the capacitor at a speed of v0=2.81 * 10^5 m/s. The proton is deflected while inside the capacitor, and the plates are long enough that the proton will hit one of them before emerging from...

I’m planning on using the ADXL375 (200g/3200Hz Bandwidth) or ADXL1001 (100g/11,000Hz Bandwidth) to measure the peak accelerations in a crash test dummy’s head during a bicycle/car crash. My goal is to sample at atleast 10,000 S/s using either a Teensy 3.6 or a Rasp Pi3. The dummy will be...

Okay so as you may have already guessed I'm really new to this site (as in I made my account about 2 minutes ago) and I'm really, really bad at maths so I need a lot of help with this question. I'm not even sure if this in the right sub-forum but if it isn't please relocate it to the correct...

I am a fourth year biomedical and mechanical engineering student and my final project has to do with designing a crash test dummy. The end goal is to mount the dummy on a bicycle and launch it at ~20kh/h, then it will be struck by an automobile driving at ~30km/h. Various different impact...

Hi folks, I've got everything I need to write a paper on the effect of constraints on passwords... except the math. I actually could write it, but the math would make it much meatier. Here is what I know about math. If the answer to a math problem is obvious, it is probably wrong. If the...

When fired, a slug's acceleration down a barrel produces an equal backward force. I get that. What I DON'T get, is why there is no rebounding force counter to a slug's impact by the material being struck? The material/molecules simply get impacted and pushed via the force generated. Why is there...

From CNN: Powerful Hurricane Irma is rapidly intensifying in the open Atlantic and poses a major threat to the Caribbean and potentially to the United States next week. With the storm still five days away from the outermost Caribbean islands and at least a week away from any potential US...

Homework Statement A projectile, launched at A with an initial velovity of 24m/s at the angle θ, impacts the vertical wall at B. Compute the angle θ that will maximize the height of h of the impact point. What is this maximum height? Homework EquationsThe Attempt at a Solution I guess I have...

A ceiling fan has kinetic Momentum in 1 blade hitting a fixed target. Would the design allow the other blades to flex , reducing target impact? If the 4 blades are combined and bolted together at same velocity is different Momentum delivered? Similar q : a human arm is about 8kg and a sword...