performance Definition and 259 Threads

Ok, I am an engine builder, building performance and race engines up to as much as possibly 5000 HP. I enjoy playing with cars, and have fitted my 1962 Chevy Corvair with EFI, Distributorless ignition, 4 wheel power disc brakes, etc. No one makes kits for any of this so I simply machined and...

Found this paper regarding performance of Tesla turbine. At the page 23, a formula regarding possible power output from a Tesla turbine is given. But, I want to know how to deduce the area given the formula. Tesla turbines are discs placed one after another with specific gaps in between the...

Lately it seems my Windows 10 computer been getting more and more sluggish. Checking on the task manager, it appears that the disk usage almost constantly stays at 100%, and that the System task is the biggest consumer. It is backing out applications I am using at the time. Is this normal...

In what condition and how definitively galvanized steel is lower in mechanical performance and counts to be ruled out replacing high carbon steel ?

Hi, I need to clarify few points about the text quoted below. I'd appreciate it if you could help me with the queries. Source: Computer Applications to Library By Kole Lambert, Page #169 Question 1: It says, "For embedded systems, the highest performance levels are often not needed or...

Consider mixing ice water with the hot water and vice versa so that the two reservoirs are closer to the same temperature. What will happen to the mechanical/thermodynamic efficiency and ideal Carnot efficiency of a heat engine?

I am comic fan There are several fiction character with electricity ability. Like Sasuke and Kakashi from Naruto , and Killua Zoldyck from Hunter X Hunter, they use membrane concept of electricity to cover their bodies, which helps the electric nerve pulses to run at the electrical membrane...

I currently attend a very large state school which is one of the best physics schools in the state, and I'd say ~top 50 in the USA, and I am working towards an honors bachelors of science in physics. I am in my 5th semester, which at my university means E/M I, CM I, Math Methods II, as my core...

If I orient my refrigerator such that the condenser coils at the back are facing a glass door (least insulation in room, cold outdoors) will CP increase? CP=Qc/(Qh-Qc) so Qh-Qc will be smaller thus CP larger. Could this damage refrigerator?

I want to build a high performance computer optimized for FEA. If anyone has any suggestions or experience with this, please chime in. I'm looking for suggestions on processors, RAM, video card, ALL of it!

I think I calculated part a correctly by extracting the cp (specific heat) of water from the table which is 4.188 Then calculated Q_dot by simply using the equation Q=m*c*deltaT=10.47kW But I am stuck at part b, I know that the heat extracted from the water is the same as Q_L (rate of heat...

Hey! :giggle: Some people assume that a specific car model does at least $\mu_0=120$ km with $1$ Lt benzin. $10$ independent tests give the following results: $$104, \ 96, \ 80, \ 100, \ 108, \ 100, \ 112, \ 120, \ 130, \ 132$$ (a) Give the Null Hypothesis $H_0$ and the alternative...

USB 3 was heralded as the next best thing to sliced bread and, imo, has been marketed in a not - too - honest way. It's not always as useful as the bare numbers suggest. I know the same could be said about 1GB Ethernet but Ethernet can handle all sorts of rag tag and bobtail traffic streams and...

Is China allways first at PISA test because they have the most people in the world so statistically they must produce the most number of talent children? Or they have the best education system?

Summary:: How to combine two formulas to find the material index Attached is the problem I am having trouble understanding. I have been able to do the first two combinations by transposing for A in the mass equation then subsituting into the stress equation. The next combinations (in red box)...

Black powder has specific impulse of around 80s, while rocket candy has up to 130s of specific impulse. Does that mean I could replace the propellant in a BP cartridge with 80/130 of the weight in rocket candy and obtain the same performance in an idealized gun? (as in without considering...

I thought that there was a standard placement for disc brake calipers on the front and back wheel assemblies for high-performance sports cars. I thought that I usually saw them placed at the back of the front wheels and the front of the rear wheels, but lately I've seen the opposite and other...

I've been learning about quantum computing for the last year and I can hardly believe what I read and hear. However, assuming that no big technical hurdles get in the way, I do think that the promises will become reality someday. It is becoming a bit clearer to me, but it's a very difficult...

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Hi. My question is for now why the equation of x as a function of time for phase of motion ab is ##x=50t-375##? Shouldn't that be ##x=375+50t##?

Hello everyone, Attached is the homework problem (FluidHmk.PNG) as well as the attempt (Attempted 1 and 2). Just wanted to know if this is method to approach the problem Thanks in advance.

Some jet engines have turboprop variants, and turboprops are rated in horsepower/watts just like piston engines. It's also possible for propeller engines to be mounted in puller and pusher configurations. While it's not possible to directly compare different engine types, what would happen if...

I would like to know if there are any Physics Instructors or Professors who may believe that Queuing Theory as well as Relativity Theory may be relevant to CPE where communications platforms are moving at relativistic velocities with respect to (wrt) each other?

Homework Statement I need to calculate the error of an average value (N for diffraction grating). My results were 4 different average angles. With which I calculated their uncertainty using std. Using equation (1), I found the number of lines per meter (N) with a known wavelength (λ) and the...

I haven't given much thought to the physics I studied in college a long while ago but found myself pondering some things recently and wanted to explore some thoughts... figured it might be a fun area to discuss and you might help point my brain back in a good direction... I regularly...

Hello everyone! I originally decided to be a physicist when I took an online course in Astronomy which talked about the greatest unsolved mysteries of the universe. After coming to university and conducting research in Particle Physics, I think I like it better and would pursue it instead...

I have a question for which I can't seem to find a satisfactory answer. We do a lot of intense real time processing of audio signals in my line of work. (Generally programmed in C) I am a mechanical engineer with only a rudimentary understanding of the process that goes on in the software for...

Homework Statement Homework Equations [/B][/B] 3. The Attempt at a Solution Here's my solution attempt: NOTE: Evolution 2 to 3 is really an isothermic process, but in the diagram shows as an politropic process. 4. Further Questions But it isn't giving me logical values of COP...

Suppose the performance of an antenna is calculated. How about its complimentary antenna?

How does the emission cross section of an emitting atom (such as Yb atoms in glass) affect the laser performance, namely the slope efficiency (signal power vs absorbed pump power) and laser threshold? Thanks a lot

Homework Statement Your company needs to install a cold room which will maintain a temperature of -15 degrees operating in a room where the temperature is 20 degrees. A new member of staff has considered the specifications of two manufacturers and asked you to check their figures. Explain what...

Title pretty much summarizes it. I know I can use the binomial distribution to calculate the chance of equal to or fewer than a certain number correct on a yes/no task where there's a 0.5 probability of being right on any trial. But what if you have 27 Yes/No trials where Yes is the correct...

I am trying to model a real heat exchanger in simulink. I don't have the geometry data. But I have UA curve with me. If I have developed the model with UA curve, will it be dynamic in nature?

Hey! :o A teacher wants to find out if the order of the exam tasks has an impact on the performance of the students. Therefore, he creates two versions ($ X $ and $ Y $) of an exam in which the exam tasks are arranged differently. The versions are randomly distributed so that $ n $ students...

Hello Physics Forums! After almost a year of haggling and research, I think I have successfully made a engine simulation spreadsheet! :oldbiggrin: I have simulated the Nissan KA24DE Engine with two different cam profiles: As far as I'm concerned, there is still a lot of work to be done...

When drilling a thick peace of steel I noticed the drill bit would cut through much faster when it was cool. The difference was minutes versus seconds! Is this a known phenomena in machining or was my drill bit simply contaminated with something or maybe other factors played a role? I've heard...

Homework Statement I have a project to research the effect of surface roughness on wing performance. I found mostly that roughness leads to increased drag on a wing, however came across a website that briefly spoke about how recently researchers have observed how carefully selected roughness...

What would you think is the best mentality to have while having a career in say, HEP? What do you think of seclusion? And what would be the best working environment? Comfortable office? Collaboration? (YES!) Take mind off physics once a while?

Homework Statement I am currently trying to do a literature survey on my project task 'effect of wing surface roughness on wing performance'. I have been struggling to find many research papers that are of a similar experiment to mine, however i have come across many that investigate the effect...

I'm trying to do some rough estimates of how much additional performance a steam powered warship (World War I to 1950 or so) could get from receiving new engines. I'm aware that different hull designs have different impacts on drag in the water, but for the rough estimate I'm focusing on the...

Are there any scientific evidence suggesting that athletes decline in athletic performance/abilities after reaching their late 30s? Such as in terms of speed, agility, reflexes, hand eye coordination, stamina and etc. If yes, what are they?

So i have an assignment to plan a flight from Heathrow to Glasgow and I am trying to calculate the time fuel and distance for the inital climb to cruise level and departing the airport, we have been given an aircraft manual and i have found the graph attached however i have calculated the...

I'm required to test a harizontal axis turbine's performance and plot a RPM vs Power curve. The turbine is driving a small DC generator that produces 5V at the turbine's maximum RPM with no other load on the generator. I am planning on installing different sized resistors in parallel with the...

Homework Statement The pV-diagram in Fig. P20.51 (See attached file) shows the cycle for a refrigerator operating on 0.850 mol of H2. Assume that the gas can be treated as ideal. Process ab is isothermal. Find the coefficient of performance of this refrigerator. Homework Equations K = QC/|QH -...

Hey Mech Eng Forum, I'm currently examining the performance on gas turbine and wondering: How is the performance of gas turbines (Primarily thermal efficiency and net-work output) influenced by the pressure ratio and temperature constraints? Additionally, what is the benefit of 2 stage...

Is there any minimum value of cooling water temperature for a particular system? In our plant cooling water temperature is much below the normal operating range.

Homework Statement I need to find the coefficient of a refrigerator that uses a monatomic gas and only has two steps. I know the: initial pressure of the refrigerant initial temperature initial volume and final pressure Every formula I know requires 4 steps or a knowledge of the outside and...

Andy Resnick submitted a new PF Insights post New High Performance Ultra-wide Angle Lenses Continue reading the Original PF Insights Post.

There are a number of fusion threads, but no ongoing coverage of progress in the space, which continues apace. It would be useful to maintain a summary of the current efforts and the high water mark performances achieved. Afaik, the rate of gain to date suggests that performance (measured by...

Hi, everyone! I'm doing a research in gap conduction calculation models in popular nuclear fuel performance codes. I want to make a sensitive analysis in their behaviors, but unfortunately, I just have access to FRAPCON package. is there anyone who can help me to gather some of the codes...