Rpm Definition and 243 Threads

Homework Statement A bug crawls outward from the center of a compact disc spinning at 190 revolutions per minute. The coefficient of static friction between the bug's sticky feet and the disc surface is 1.4. How far does the bug get from the center before slipping? Homework Equations...

I am trying to use an engine running at 900 RPM to power a generator that needs to run at 1800 RPM ( This will go through a pulley) My question is is half the available horsepower to the generator lost since the RPM's are doubled? In other words, do I need to double the horsepower of the...

Dear electronic gurus, (2 part question) I want to check that: If i got a 12V motor (such as http://scientificsonline.com/product.asp_Q_pn_E_3041860" ) would i be able to adjust its RPM if i got a: 12V dimmer switch box...

Hey, I'm trying to build a stroboscope for measuring the RPM of a few different fans. So far I've tried using LEDs but haven't been very successful. I tried using a function generator with square pulses (I tried both 20% duty cycle and 50%). So I started at 1 Hz and kept on increasing the...

I am building a small device that operates underwater so I am powering it from this...

what size shaft is required to transmit 100 Hp @ 1000 rpm ,if max shear stress is 10,000 psi .angle of twist must be less than 1 degree /ft .shaft is made of steel.

Now, everyone knows that motorcycle engines work at much higher rpms than car engines. They also produce lesser torque than a car, because (and correct if I'm wrong) bikes don't have as much load on them as cars do. Can anybody tell me what goes in an engine that decides that when power is...

I need to calculate the rpm of my flywheel on my wobbler so I can determine which flowmeter to use. Any suggestions? Is there any way to calculate rpm without running the flywheel?

Hello all. This is my first post as I need some help. I'm building a "barn Door" project which I'm sure you all know is a device to track the stars. With the measurements I've built it to I need to drive the screw at 1 RPM. I'm finding it very hard to get a 1 RPM DC motor either...

http://www.sciencedaily.com/releases/2008/11/081114081213.htm Up to now, industrially-deployed motors have normally reached 250,000 revolutions per minute. Now, however, researchers from ETH Zurich’s Department of Power Electronics have developed a drive system in cooperation with its...

PMA and High RPM from a turbine... Hey Forum, I am working on a plan to build a recharging setup. What I want to do in theory is take a jet turbine or a smaller RC turbine that burns bio diesel and turns at around 60,000 RPM. I want to take this high speed rotation into a chain or belt...

Homework Statement Suppose you're operating a machine with two motors. If the two motors are not operating at the same rpm, you will hear a periodic variation in the intensity of the sound-that is, beats. Suppose the tachometer that indicates the rotation rate of one motor is malfunctioning...

In an old-fashioned amusement park ride, passengers stand inside a 4.9-m-diameter hollow steel cylinder with their backs against the wall. The cylinder begins to rotate about a vertical axis. Then the floor on which the passengers are standing suddenly drops away! If all goes well, the...

I am looking for a cheap device to check sensor function, the sensor is detecting at 120 rpm and should give a 24v output. If there is a circuit i could build my self that would be great. Thanks.

I’ve been searching for an answer to this question on the web for 3 hours. Thought I would find it quickly, but, noooooo. I’m trying to understand why crankshaft torque falls off at low RPM in normally aspirated piston engines. I think I understand the high end of the torque curve OK. At...

Hello all, Is there anyone out there who can help me out? I have developed a drive system for a generator, but... the big but... in need to know how to build the appropriate stator for it. Assume this is of the windmill electrical generating variety, where magnetic coils produce AC...

can anyone tell me how to solve for the voltage output in a generator and all the variables needed to solve it. What if I only have the RPM can I solve it? thanks

If I have an air compessor that uses an 11 horse power gas engine. How do I know what size electric motor, and what RPM will do the same job?

And how would I do all the math for how much HP I would need to turn it based on its weight etc.? Would I just use a normal 3 wave alt for high RPMs? Like roughly... 10-15000rpms

Hello guys, I am curious about the effects of increasing the number of coils on the armature of a DC electric motor. Say if I switch from a coil from 80 turns to one with 160 turns (made of the same material) would the rotational speed of my motor decrease for the same voltage? I had several...

Homework Statement How fast (in rpm) must a centrifuge rotate if a particle 7.0 cm from the axis of rotation is to experience an acceleration of 100,000 g's? My variables radius= 7 cm or .07m radial accel= 100,000 g's or 980,000m/s^2 or 98,000,000cm/s^2 V= I think I need this to get w...

Hi, everyone I am a long time reader but this might be my first post. I am currently in a Senior Design Project and doing research for my project. I am doing a rotating shaft with flow through the middle of the shaft to a exiting hole on the other side radially out the shaft. ( I can explain...

Hi, i need help figuring out what to look for in a motor given certain specifications. If I am browsing for a motor that is able to spin at 3500+ rpm while holding 200 lbs. of weight, what attributes/values do i need to pay attention to?

Imagine a ball launcher which is composed of two rubber wheels that spin in opposite directions such that a ball that is fed in, will be launched from the other side at X m/s. I am trying to figure out how many RPM the wheels need to be spinning to launch a ball at Velocity X. Knowns: The...

I need help working out the RPM of the motor/gearbox and torque from the following details: The temporary drive rigged up is running at 0.2 metres a second, which is a little faster than the speed we usually ran our broken Lenze drive. We bottle 2 sizes of glass bottle, 1 litre and 1/4 litre...

[b]1. [b]1. The rear wheels of a tractor are 4 ft in diameter and turn at 20 rpm. a. How fast is the tractor going (ft. per sec.)? b. The front wheels have a diameter of only 1.8 ft. What is the linear velocity of a point on their tire treads? c. What is the angular velocity of the front...

It's commonly believed that running your car at a lower RPM (highest gear possible), will get better gas mileage. We hear this from our parents and friends, and we assume it's true because it seems to make sense, but has anybody ever done a study to prove this? I'm asking because I monitor my...

me and my friend are having an argument about this. I say that because frictional force is less than or equal to the coefficient of friction times the normal force, and that neither the coefficient of friction nor the normal force can be increased while an engine is running(until it's oil is...

Homework Statement A flywheel has shape as a homogeneous cylinder with mass m = 40,0 kg and radius r = 0,50 meters. The cylinder is rotating round the axis of symmetry, and is runned by a motor with constant angular velocity (w0). When the motor is switched off, the cylinder is affected by a...

1. Homework Statement theta(t) = 2t^3 + 5t^2 - 2t + 1 Find the angular velocity in rpm's at t = 2s if the radius of the circular path is 30 cm Basically I want to kno if i did this part of the problem right b/c my professor didn't give us a key for the practice exam 2. Homework...

Does anyone know what the highest rpm in the universe is?

So I'm driving this super mini on diesel and I observe several differences with normal petrol cars. At low RPM, some 1700-2000 cycles, the engine is super effective, the torque and the excess power is awesome, while the fuel consumption is unreal low. However at higher RPM, this surplus...

What's the highest rpm centrifuge on earth.

Linear RPM vs Time = ?? Horsepower I have graphed some sampled data taken from a car on a level road, traveling its rpm range (from 2000rpm -> 8000rpm) under full acceleration, and the graph shows an almost linear change in rpm over time. For the sake of example, let us assume RPM = time...

consider a piston in an engine with a stroke of 86 mm and RPM 8000 which gives the frequency of sound it is producing(due to compression and decompression) to be 133 Hz and wavelength 2.57 m. Then the pressure amplitude turns out to be 20000 Pa and the intensity of the sound wave to be...

hi does anyone knows what exactly is a motor's nominal torque. for example, if i have a variable speed motor that runs from 0 to 3000rpm and its rated power is 3hp, then are there various nominal torque for different rpms? then which should i choose to if i need to connect it to a...

Theoretical Deposition Rate based on RPM -- Help ARRGGG! Hey guys, what's going on. I have recently started doing research for a professor here in the field of nanotechnology. It turns out that it's not all small robots and stuff. Right now I'm working with thin film coatings. ANYWAYS, we are...

A motor runs at 1450 rpm. Attached is a gear that has a gear module of 5 mm, and a mid tooth-diameter of 95 mm. This wheel is toothed up with a second wheel who's shaft drives a third wheel. This third wheel is then toothed up with the fourth and last wheel who's shaft runs let's say dryer...

A car's typre has diameter 570mm, and the height of the centre of the axle above the road is 260mm for the front wheels, and 270mm for the rear wheels. Find the speed of the driven wheels in rpm when traveling at 60km/h. The answer is 61.539rpm. I can't get this answer... can anyone help?

A centrifuge is a device in which a small container of material is rotated at a high speed on a circular path. Such a device is used in medical laboratories, for instance, to cause the more dense red blood cells to settle through the less dense blood serum and collect at the bottom of the...

I have a Digital Multimeter (DMM) which also measures frequency. Can this be used somehow to show RPM's of a DC motor while it is running at various stable speeds? Or is there an inexpensive device which can be used to show RPM's? If I have to build a device, my thoughts are to mount a sort...

I need to know whether to invest in a new lighter axel for a go kart Before I take the plunge, I'd like to get "some" kind of idea of the kinds of gains one can expect from this kind of change. The conditions as I know Them. the 5Hp engine achieves max torque at 5200-5400 RPM...

I can't find formula for determing the number of rotations a wheel makes in one minute. Diameter = 26" Traveling at 20 feet per second. is there a formula for RPM? Also need the formula to determine angular velocity. thanks