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Calculating Speed?

If you have an object with a mass of 2000 grams, and it has an average force of 635.029 kg pushing it for a distance of 6.096 meters before it becomes a free-flying projectile.  How fast is the object traveling after the 6 meters and how do you calculate it.

Question by    |  last reply

speed controller ?

You can make a washing machine motor with the module and taco run with a potentiometer switch to give you speed control over the motor I have the planes for a hot point motor but not the motor im using !! does anyone have the no how as to with leads to connect to contact

Question by rumsey    |  last reply

speed of light?

I want to know the derivation of relative velocity formula used by Albert Einstein to prove that nothing can exceed the speed of light. Is there any simple derivation? please help

Question by deepakmurali    |  last reply

Speed Cameras

Personally, I'm on the fence on whether or not these are a good idea in the first place. Should people be speeding in the first place? If yes, why? Having a large speed differential with the rest of the traffic can be quite a dangerous situation.... Why am I on the fence? Because we, in addition to the UK, are already an endemic surveillance society (allong with Russia and China) CITE - it's sad :(]. I'm also anti rfid ID (including the new US passports :/), the Luddite tradition of machine breaking is alive and well in its country of origin. According to a report, a group calling itself MAD -- or Motorists Against Detection -- have taken to setting autonomous traffic cameras ablaze across the United Kingdom, and are detailing their exploits on a website (of course). The group's "PR" claims they have been active since 2000, and have destroyed over 1000 roadside cameras. Says the group's leader, Capt. Gatso, "The vigilante anti-speed camera group have announced a summer of MADness which will see them target for destruction all speed cameras in the UK. It's now going to be a period of zero tolerance against all speed cameras." The gang of disgruntled drivers also plans a day of action called "National Cover-Up Your Number Plates Day." Guy Fawkes would be proud.Here's a website for the torched camerasI'm interested to hear the opinion of those of you in the UK... Of course, in addition to everyone else.. Opinions on speed cameras?

Topic by trebuchet03    |  last reply

Speed sensor

I have a 60 tooth ferromagnetic ring gear with a speed sensor attached. Each passing of a tooth creates a pulse in the sensor sending a signal to the ecu for calculation of attained rpms. It calculates the interval between the teeth to obtain the rpms, thus determining when to kick in the rev limiter on my 06 polaris ranger XP 4x4. Is it possible or even practical to eliminate every other tooth to "fool" the sensor into a lower rpm reading, and creating higher rpm levels within the motor?

Topic by hiatt65    |  last reply

What happened to the 'speed' in Speed Contest?

Now, I know that these contests are shorter than ones like the Laser Cutter contest, and the Science Fair, but nearly 19 days long? I thought that speed contests used to be a week, no more. Is there a reason why they are extended now? Thanks, Bran E.

Topic by Bran    |  last reply

speed vs. distance?

Hello All, I am considering building a electric motorcycle in the next year, all the Instructables I have read on the subject boast top speeds of 70 mph and a 10 - 20 mile range. I live in a small city in Canada where the maximum speed limit is 50KMh(~30mph) and the city is not even 7 miles across, also there is nothing outside the city that is close enough to get to with a ev such as this. My question is how does the speed and distance connect, for example, if I was to travel at half the speed would I be able to expect to get double the distance?

Topic by alexm    |  last reply

wind turbine speed?

i have herd that the minimum amount of wind required to power a (homemade) wind turbine is 10 m.p.h. is that true? and whats the maximum wind speed?

Topic by Sun Gear    |  last reply

Speed of sound question !!

My friend and I were debating : If somebody sitting in the back of a plane cockpit going faster than the speed of sound ( the whole plane that is, imagine it was the SR71 ) insults the pilot at the front will the pilot hear it and turn around to punch the guy sitting in the back? This one might be more understandable: Can someone sitting in the front of a super sonic plane hear the guy in the back, without the help of microphone and all that crap. My friend thinks it is impossible becose the plane is going faster than the speed of sound and the sound from the guy at the back will not go fast enough for it to catch up. I think that is total nonsense Anybody knows the answer ????

Topic by vince086    |  last reply

Speed Challenge Group

Join our new Speed Challenge Group to keep up on what's happening with all of the challenges run by the editors on the site.  There you can see what challenges are currently running (sort by recent), and all of the challenges and winning entries from the past.  You can also start forums to discuss which were your favorites and what you'd like to see in the future.  By joining the group, you should be able to get updates when a new challenge is submitted.  You can also add it to your RSS feed so you know you'll never miss a new challenge!

Topic by scoochmaroo    |  last reply

Speed Limiting hinge? Answered

Ok, I'm building a motorized projector screen, almost exactly like this: , except on a much larger scale. The actual screen will be made out of blackout cloth (what the back of curtains are made out of), and the screens construction will be similar to this: . The screen's size will be somewhere around 20x20 (feet), because it will be used in a fairly large auditorium. The screen will hinge up and reside (when not in use) above the stage. The top of the screen will have some hinges attached, so the screen can "fold up" into the ceiling. Toward the bottom, on the back of the screen, there will be a steel cable attached to the frame. This steel cable will be fed into an electric winch, which will be mounted on the ceiling. So, when the electric winch is activated, the screen will either hinge out, or it will hinge up into the ceiling. I know its hard to understand, I've done all the explaining I can. Ask questions if you have to. Anyway, the problem is this: What if this steel cable broke/got frayed and snapped/got chewed up by a darn rat, etc? The projector screen would come hurtling forward, knocking out anyone in its way. So, I need something that limits the speed that the screen can be lowered. I need some kind of hinge that limits how fast the screen can be lowered, so if the cable does snap among other things, the projector screen will make a graceful descent and people will have enough time to get the hell off the stage. Now, Do I think the steel cable is going to snap? Hell no. In fact, the steel cable I'm planning on using will handle over 1000 lbs. The total weight of the projector screen? Maybe 70 Pounds, at the most. These speed limiting hinges are just for that "extra" step of safety. So, does anyone have any suggestions?

Question by tyler9613    |  last reply

what is the speed of dark?

Question by Travpena    |  last reply

change the speed of the Servos ?

I new in arduino and i'm building a robot arm how do i change the speed of the Servos ?

Question by mogy336    |  last reply

Gs to Speed Converstion

I am looking for the math equation that converts G load to speed using Arduino (  I am building a high power rocket data logger/controller. I need to know the speed by using accelerate of the bird. Yes I might be able to use GPS info, but at super sonic speed GPS can not keep track of the speed. The bird is a 2 stage bird. I want to stage when about 40% of the speed has bleed off.  Thanks Rocket Nut

Topic by Rocket Nut    |  last reply

Hyper Speed Cams

Ok heres my problem im making some videos and i was wondering how can u make a video go slow mo ~does any one have any software for this? ~is it possible ~can i do this without hyper speed cams? Thanks Peace~ Zero

Topic by zero0928    |  last reply

Low Speed Motor?

I want to make a baby night toy with multi color LEDs and a rotation device. For which i need a low speed motor. Can someone help me find such a motor or give any idea on how an ordinary motor can be used for this purpose? thanks in advance for all the feedback.

Question by muhammajunaid    |  last reply

Increase running speed

I don't run very much. I never was all that good at it. Lately, though, I have found the need to improve that ability, specifically my endurance at speed. I can slowly jog a mile, sure, but haulin'-ass-away-from-an-amgry-man-with-a-knife-speeds don't last much longer than thirty yards, if that. I'd like to improve my overall speed if possible, and especially increase the distance that I can cover flat-out before I keel over. I'm not going to be running a marathon anytime soon, but I'd like to be able to get farther than average, as fast as possible, on demand. Any tips for training or proper form? I live at roughly 5400 feet, but I'm just a short drive away from 14,000-foot peaks. I would also like to improve my off-the-line times--in other words, acceleration. If I were to need to run between ten and twenty-five yards, I can do that at my top speed as is, but that speed is not as fast as it could be. I'm generally not even up to full speed until eight or ten yards past the line. Suggestions?

Topic by Rishnai    |  last reply

Anti-speeding device?

I am going to be buying a new motorcycle soon after spending several hundred dollars clearing up my previous youthful errors with my last one. Anyways, I am thinking about rigging a bright LED to the top of the windshield that comes on when I go above a certain speed. Right now all I can think of doing is like in the old movies when then make a time-bomb is drill a hole in the face of a clock (speedometer in this case) and have a wire come in contact with the speedometer when it reaches a certain speed. If anyone can come up with a more efficient and elligant idea and how to do it please email me at Thank you ahead of time, Chris

Topic by cjp91068    |  last reply

Gameboy Volt / Speed ?

Hi, I am working on a little project with my olde Gameboy Color ! I am taking it out of its case, and building a wooden / bronze one in SteamPunk Style. Now to get even Nerdier i am considering to build a "Stirling engine" and power the little machine with a Dynamo attached to it! However this might turn out, i would like to know if the dynamo generates more than 3V if that would speed the Gameboy up, or simply fry it? I will add a Good Resistor to prevent that btw :p

Topic by Schoening    |  last reply

Sailboat Speed Comparisons

Portsmouth Yardstick is a rating system so different boats can race and supposedly the best skipper will win. It's a good way to see how fast different boats go around a triangle course.They've got hundreds of types listed and rated.I've written up some observations illustrated with videos here

Topic by TimAnderson    |  last reply

can i speed up my modem speed?

am in rural kenya & i use a modem to browse. i wonder if i can speed up internet connection by buying a router or whatever they use in big cybers. can anyone advise me on internet connections available in kenya or the modem can be speedup by buying any gadget to plug it in. dont worry am poor in networking.

Question by mauricewarebee    |  last reply

There's high-speed photography, and there's high-speed photography...

High speed bullet photography is cool - the precision of catching the bullet flying through a carefully-placed target. But how about hitting a moving target?  How about hitting a single drop of water? Dutch photographer Alexander Augusteijn can do it, apparently using normal flashes, but with the timing controlled by computers. Lex Augusteijn Photography via PetaPixel

Topic by Kiteman    |  last reply

How to make a speed meter to stop cars from speeding?

Ok folks, I live along a street where people come blasting through, and I want it to stop considering there are kids who kindof like to play on it. Here is born my idea: A speed meter that sits in my yard. If it senses a car going faster then about 30 MPH, it will automatically set off a siren, scaring the crap out of people and making them slow down. I don't want to hear about how this may/may not be illegal, I'll go to jail if its for the sake of saving our kids lives. So I was thinking about how to do this. An Arduino might work...but I would have to find some type of speed meter to use as a serial device for the Arduino, and after I did this, it'd be pretty easy. Just wire up a siren to a relay on one of the Arduino's outputs and away I go. Anybody know where I could find a speed meter that will work with the Arduino?

Question by tyler9613    |  last reply

DC Motor speed controler

Hi all Can anyone suggest the best way to replace the variable speed trigger of a 18v battery drill, with a remote from the drill adjustable speed control. I want to control the speed and have it stay at the setting until I turn it off or adjust the speed. The drill will be clamped to a board with no battery and powered by a power supply. Thanks for any advice Les

Topic by Les1951    |  last reply

New Speed Contest: Toss It!

Show us the best paper airplane you have! Toss It! Speed Contest

Topic by fungus amungus    |  last reply

New Speed Contest Announced!

You have three weeks to make an Instructable that involves LEDs. Go!

Topic by fungus amungus    |  last reply

ac motor speed control

My uncle recently gave me a compact, functional ac motor with an axial blower attached to it. its a pretty cool thing, and i am planning on putting it in my mac's plexi case (when its built). i have no clue how to vary the speed. from what i found on wikipedia, an inductance motor cannot have speed control. how do i know if this motor is brushed or inductive?? and if its brushed, how do i vary its speed? help!!??

Topic by tech-king    |  last reply

Controlling the speed of the ceiling fan?

I have a standard ceiling fan of which the speed can be controlled by pulling the cord. As the slowest of the three speeds is still to fast, I would like somehow to be able to lower the speed. Is there any way of doing this? The fan operates at 220V

Question by nightlife31    |  last reply

Cheap High-speed Camera

Yes, I know, It's an oxymoron. I've always wanted a high-speed camera, but they are way too expensive. I was wondering if any of you fellow Instructablers have a high-speed camera that you've lost interest in, and are willing to sell for a low price. Alternatively, if any of you know how to make a cheap, high quality, high-speed camera, could you post an Instructable? Edit: I bought a Casio EX-F1 a while ago, and even made an iBle about it. I also have a bunch of videos here.

Topic by Spl1nt3rC3ll    |  last reply

1-Week Speed Contests

Did y'all get rid of the speed contests? I thought those were fun because of their rapidness. Or did y'all just move it to the back burner?

Topic by Bran    |  last reply

0.3mm nozzle printing speeds?

I am currently finetuning my homemade hotend and was wondering what you guys have in the speed settings for 0.3mm nozzles printing ABS? I started with the aim of reaching 120mm/s but after some hours of finetuning I am currently trying to breach the 200mm/s barrier. As I am only using a very old Mendel Prusa I am actually quite happy that I got that far. What speeds are possible with the current printer models? (not the statements on the website, real life)

Topic by Downunder35m  

Question regarding speed electricity

Hi people! I have another thing which i do not totally understand, so as usual i have asked in one of my favourite sites! :) I always had a doubt on how "fast" is electricity. In our real world, i can observe that it is pretty fast. If i turned on a switch connected to a light bulb, i can see it turned on pretty much "instantaneously". So a question came to mind, how fast it really is? Is it near to the speed of light? So, i did some googling. According to what i have found and understood so far, it is the electric field that carries information and not the electrons themselves. And electric field travels near to the speed of light( of course, depending on the medium).  If that is the case, then from the "textbook" definition of electricity, it is the movement of electrons right? But according to what i have understood so far, electrons move pretty slowly. In DC a few millimeters per hour or so(not having the exact figure in mind, pardon me) and the average displacement in AC is zero. Then how exactly is electricity so fast? I would appreciate it if someone explains it in a simple way, both on speed and what exactly is movement of electrons. :) Update: Okay, so far my questions are answered, and it seems to take off in different directions(like science always does :D). So to stay true to the question posted here, i would like to say my doubts cleared! Many thanks to people who have answered my question, Specially Dr.Kelsey and Josehf , for the information provided! I will post other doubts in new topics.

Topic by charmquark    |  last reply


I have a 12dc sever fan installed into and old fridge to be made into a jerky dehydrator. what i need is a simple TWO POWER WIRE IN and TWO FAN WIRES OUT speed controller as the fan empty's the air from the fridge in 2 seconds flat. what i need is a controller with three speeds and an OFF. i can make one very easily from a detailed schematic but please keep it simple

Topic by joypad    |  last reply

A-Jax - Speed - Web Developers

Why use slow flash when faster better ways are there? AJax is great, fast, and does the job. Here is some simple code for your site: xhr = (window.XMLHttpRequest) ? new XMLHttpRequest() : new ActiveXObject("Microsoft.xhr");"POST or GET", "PAGE-URI", 1); xhr.onreadystatechange = (function() { Code to run for the result.. }); Simple yes? My site uses the code above but within lots more Javascript hacks included. My site is My js file is minimized so to get to the code just goto and the same deal with my css file..

Topic by james.mcglashan  

DC motor speed controling

HI!  I'm trying to mod my Tascam cassette recorder. I want to be able control speed of the motor. So I bought on ebay PWM controller and after installation thing don't run so smooth as I wish. the problem is ... when pot is all the way down at 7 clock motor is off, when I turn it to 8 a clock motor starts spinning and reaches its full speed at 9 a clock. and from 9 a clock to 4 there is no effect on speed. Please help me! .... my electronic skills are too weak to understand this. p.s  it is 12v dc motor and there is link for the pwm I use.;=STRK%3AMEBIDX%3AIT Thanks    

Topic by AndrisT1    |  last reply

DC motor speed controling Answered

HI! I'm trying to mod my Tascam cassette recorder. I want to be able control speed of the motor. So I bought on ebay PWM controller and after installation thing don't run so smooth as I wish. the problem is ... when pot is all the way down at 7 clock motor is off, when I turn it to 8 a clock motor starts spinning and reaches its full speed at 9 a clock. and from 9 a clock to 4 there is no effect on speed. Please help me! .... my electronic skills are too weak to understand this. p.s it is 12v dc motor and there is link for the pwm I use.;=STRK%3AMEBIDX%3AIT Thanks

Question by AndrisT1    |  last reply

Cheap High Speed Camera

I've had this idea about a cheap high speed camera using say 10 of those small action cams, like this:;=item2a16846d30#ht_4895wt_952 What you would do is hack the Start/Stop switch and hook it up to some sort of controller that starts each one of these 10 cameras about  3.3 milliseconds before the next one, thus having each frame from all the cameras to be 3.3 milliseconds apart from each other, which is 300FPS at 720p for $158. The cheapest HD 300fps camera....   EVER, not that i can make it. The cheapest equivalent is around 2K.

Topic by williamp321    |  last reply

Increase the speed of an electric motor? Answered

My electric bike, seen here, was built for my senior project. I was limited on motor choice, and had to go with the best I had, an old powerchair motor. After 2 successfull attempts at building an electric bike, I have discovered that it is impossible to go faster that 25 mph with with one of these motors. As you can see on my instructable the bike has 6 speeds, with a top speed of 20mph in first gear. however, when I shift gears, the motor rpm's decrease instead of the speed increasing. I have heard before that it is possible to run an electric motor at higher voltages than it is rated, so I was wondering, if i could add a seperate switch and a "booster battery" of sorts, that as long as I monitered the voltage so as to not let exceed 24 volts, if this would be feasible. My only other option would be to add a second motor in parallel with the first, and on the same drive belt. The first option would be the easiest, if it could work without damaging the motor. Any help would be appreciated. Thanks, iloveairsoftstuff

Question by the mechanical engineer    |  last reply

Speed Record for Cal 40

Any one know of top speeds hit in Cal 40? I presume this would be a transpac speed.

Topic by pnelson    |  last reply

How speed govornor disabled

My Hyundai xcent prime t plus CRDI. Company fitted speed govornor. Limit maximum 80 kmph. How to speed maximum 120 kmph highoway

Question by ParthaT1  

Shutter speed on Canon Ixus?

Hi guys, l'd like to ask if it is possible to make the shutter speed faster (eg. 1/1500 or something)  on the Canon Ixus 125 HS camera. If so, I'd like instructions for it and images if possible Thx in advance 

Question by NebulaIX    |  last reply

Speed controlled industrial fan

Hi all, For an installation I need a speed controlled fan that I can control via a microcontroller. Is there any industrial fan that you know that allow to be controlled with eletrical signals rather than the usual manual control? thanks a lot!

Topic by amicoleo    |  last reply

Reduce speed of an RC motor?

I took apart a RC helicopter and stripped everything so its just the motor operated by remote. I plan on attaching a camera to the end if the motor and my goal is to make a pan/rotate base mount thing. However even on the slowest speed (lowest on the throttle) the motor spins way to fast. Is there anyway to control the speed or slow it down? Please Help

Question by jasonduiella    |  last reply

Nema 17 max speed?

What is the max speed of a NEMA 17 motor like this one? I will use a easydriver+arduino. Would there be a different stepper driver i should use (that is still cheap)?

Question by headslant    |  last reply



Question by SNIPER,LA    |  last reply

Adjustment of the speed of a DC motor Answered

I'm working on something that requires a very low speed motor (~.5-4 RPM). I found a motor that runs at 1.5v @ a maximum of 7rpm (5040RPM max with 1428:1 ratio) I need however, something to lower and raise the speed of this motor. I know that people say PWMs for this, but the only one I can find is a 12 volt and has gotten mediocre reviews. Could I use this 12 volt PWM in this system, or could someone point me to a reasonable PWM that would work?

Question by sblaptopman    |  last reply

How to control the speed of this motor ? Answered

I have this spare Dayton Shaded Pole Motor that I would like to use for a project.  When the motor was removed, just two wires are attached to it to which I attached an adapter plug.  When plugged in to a wall outlet, it obviously runs at only one speed.  I was wondering how I could control the speed of the motor thus enabling me to lower the speed.  Would it be possible to add a dial to lower the speed?   I saw a video on youtube titled How to make a Simple Speed Controller (link: and was wonder if this would work for my motor? In the video, the guy uses a Switch, project box, and potentiometer.  However, should a rheostat be used instead? (someone posted that in the comments to the video) So, let me know what you think, and how I should go about doing this. Here are the specs of the motor: 1/40 HP 1550 rpm 115V 60 Hz 1.1 Amp Class A Ins, 40 degree C Max. Amb. Cont. Duty Thank you.

Question by Schaf77    |  last reply

Slow PDF Download Speed

I'm running Macs, all with OSX 10.4x of a Verizon FIOS router (new) using the latest version of Firefox. Your pdf downloads are EXTREMELY slow, although pdf downloads from other websites are NOT. What gives? Is there a setting or some tweak I can do to speed things up? Neil

Topic by neilsky    |  last reply

Building a makeshift speed controller

Hi all, I recently posted about issues with my treadmill. I thought I'd fixed it but it has multiple problems. I've decided rather than go down the route of costly replacement boards, to go for a chinese universal treadmill controller.My question is, could I make a makeshift speed controller using the components from the circuit boards? (it may take 4 weeks for the chinese controller to arrive, so would like to continue using the treadmill)I'm guessing I have all the components needed to change the 240v AC to 130v DC, could I then use a potentiometer to vary the speed?I've added a photo of the board, not pictured is the big transformer.Any help greatly appreciated :)

Topic by dimmaz88    |  last reply

Variable Speed Stepper Motor

Hello Everyone, I am looking for some help to make a controller to drive a stepper motor using a potensiometer. I want to be able to vary the speed from 0 to 100rpms or however fast the stepper motor will go.   I have a bi polar stepper motor that I am using.  If anyone could help with this it would be great!  Thanks

Topic by TWMCNANEY    |  last reply