Recently I read about Saab's experiments at closed loop spark advance, and it got me wondering. If you are controlling spark advance to maintain a constant peak pressure position of 20 deg after TDC is it possible to get into a situation where detonation or pre-ignition is possible. It seems to...
An elderly neighbour has just bought a cheap store-branded electrical convector heater. Basically it's a mains power switch, a mechanical thermostat switch, and a resistive heater element in series. (There isn't a fan, it relies on natural convection).
The thermostat contacts are producing...
I put a hamburger(wrapped by foil) into microwave and pressed start. I noticed an electric spark near the foil's surface. How can we explain this incident?
ps. sorry for my english
All things being given - separation, breakdown V, temperature, and so on... If I have two pins and they are both connected to a high voltage capacitor & switch - (supposing the circuit has zero resistance aside from the separation and air)
How much current will flow in the spark which arcs...
Does a spark gap increase the current in a circuit? My thinking is that the surrounding air is ionized and any "stripped" free electrons would add to the current.
Hi, I am working on a school design team where we are building a small scale formula car. I am a member of the engine group, and am tasked with CALCULATING the minimum spark energy required to start combustion in our engine. I know there is an official term for this, (required spark energy?)...
Hello,
I have moved that question around in my mind for quite a while now. I have gotten several datasets from amateur high altitude balloon flights in which the Geiger Counters onboard delivered either no data or excessive count rates, and this occurred almost every time when a balloon...
If I wanted to know how to find the magnetic flux through a loop, I'd need to know the current flowing near it. If that current is in the form of a spark, how do I represent that?
The spark is nearly instantaneous, and I've got no idea how to determine the number of charges which flowed...
Homework Statement
suppose we have a coil sitting on a desk (with radius =1), and then a spark passes by the side of it, in such a way that the magnetic flux through the coil is maximized. The coil is attached to a full wave rectifier which is connected to a very large capacitor.
There is an...
On a fundamental level, can anyone explain how a spark is created from scraping a knife along a piece of metal as done by people who want to light fires 'in the wild'?
Sorry about the intrusion as I really don't belong here as I have absolutely no background in physics but I have a couple of questions regarding lead acid batteries that I have been unable to find answers to on the internet.
First question - why does a battery spark/arc when the negative is...
Hello there, looking for some help! I am currently teaching ionising radiation to my Year 10 physics class and I have been making frequent use of our spark gap apparatus, which is an old Griffin & George unit. This has been hidden away on a shelf in the prep room along with the EHT supply...
What causes a switch's contact to spark when you use it to open a connection to a load?
I can understand why the contact sparks when opening an inductive load (inductive reactance), but what if the load is purely resistive?
3-pin (Gas Discharge Tube) Surge arrester rating "DC spark over voltage"
Could someone please help with a question about Gas Discharge tube, surge arresters rating?
I am looking at a public address audio equipment which uses a 100vrms audio lines driven from a audio transformer. Currently...
I had a drag race two stroke snowmobile that was over ported to a point that low end power was so poor that the engine was very hard starting. I put a drive socket on the end of a V-8 car starter and used 24 volts (two car batteries) for power. Being a bit nervous of the torque kickback, I tried...
Homework Statement
A spark occurs at the tip of a metal needle if the electric field strength exceeds 3.0x10^6 N/C.
What is the minimum surface charge density for producing a spark?
Homework Equations
int(EdA) = (Qin) / e0
The Attempt at a Solution
I imagine the surface as a cylinder with...
hi
i saw this page, http://sound.westhost.com/clocks/spark-q.html and he has tried various methods to quench the EMF spark from inductors. when a lot of current is pulled from the inductor during the quench the inductor magnetic field is prolonged - what is this delay called? this is the only...
Hello all,
I am studying physics at university, and I read something interesting in my book: If the electric field strength increases beyond 30,000 V/m in air, a spark will be created between the two potential differences.
This was really interesting, and being a more practical person I...
hi, i am pretty new with electronics, and i can't find any simple boost converter circuts on the enternet. i would like to make the circut THE MOST SIMPLE i can, with the fewest possible parts. for a power source, i have 9v-1w. for the output power, i would like to send a thin spark from 1...
A spark plug in a car has electrodes separated by a gap of 0.025inches. To create a spark and ignite the air-fuel mixture in the engine, an electric field of 3.0 x 106 V/m is required in the gap. (a) What potential difference must be applied to the spark plug to initiate a spark? (b) If the...
Had a bad day at work and my design for a spark generator failed, so I'm asking for help.
My requirements:
To create a spark in a hard vacuum environment (10^-6 mbarr)
To be ultra miniature (as a guideline about 1cm^3 is the space available)
Available power lines is 4.4v at 0.22A or 700V...
.
Hi all.
Some time ago I read that old competitions car drivers realized that by inserting a gap in the HV cables, the spark in the plug was "reinforced", like getting a more energetic discharge and, consistenly, a better fuel ignition.
This is a drawing about what I am talking about...
When a switch is in on condition say our home 230 volt ac switch,, and I plug in any electrical device in that on switch, there is spark , what is the reason of this spark..
please explain
HI, my friends
Lets imagine a car engine combustion chamber which is fed with an estequiometric fuel mixture (gasoline+air) with a 1mm plug gap.
Is there an aproximate algorithm to solve out what voltage is needed to create a spark, based on gas pressure and temperature?.
I don't want...
Hi all
I have a question concerning the voltage required to initiate the ignition spark in a combustion chamber.
I learned this voltage depends on the dielectric in the plug gap. The more pressure the higher voltage, the richer gas mixture the lower voltage,...and so on...there are many...
Hi
I'm trying to build a system to generate a spark with sufficient energy to ignite a freely expanding jet of methane, but with a quite short duration, ca. 20ms (if that is classed as short?) The purpose being to examine concentration fluctuations of gas (in a jet) above and below the...
I'm totally stuck on a physics problem. I've been looking through my notes and my book for the past hour and cannot find anything.
The question is
Find the distance at which an electric spark would arise between your hand and the metal doorknob if your hand carries a total charge of...
if i have calorific value of mixture, volume at time of compression, bore diameter, can i know the pressure being exerted on the pistons due to the combustion?
Hi, I am devising a way to store large amounts of electricity, but at the moment it is more like a capacitor in that it greatly tends to release the energy in a spark.
I'm trying to come up with methods to regulate the transmission of electricity from this capacitor without wasting the...
Honestly I do not think automotive techs would know the answer to this question so being said from a physics stand point about the relationship between the high voltage spark on a spark plug and compression in a engine. I have had experiances where there was spark on the plugs but the engine...
Homework Statement
Air "breaks down" when the electric field strength reaches 3 x 10^6 N/C, causing a spark. A parallel-plate capacitor is made from two 4.0cm-diameter disks. How many electrons must be transferred from one disk to the other to create a spark between the disks?
Homework...
I need to calculate the minimum distance for which a charge of some voltage will jump. Is there any equation that relates distance of a spark jump to voltage (a fairly generalised equation will do, I don't need to worry about strange shapes of the charged bodies that the charge leaps between or...
Hello All!
Quick question...
When a high voltage capacitor is charged to say 3000 volts, a spark
will jump across the terminals.
Does the spark jump from the positive to negative terminal, or from negative to positive?
Thanks Very Much!
Bill
Homework Statement
Approximately how large an electric field would be required to cause a spark in a gas at standard temperature and pressure if the ionization energy for the molecule of this gas is 1.5 times the ionization energy for air molecules, and the cross-sectional area of the molecules...
My friend and I are trying to build a very basic to get a spark plug to fire. Right now we have a plug, and Ignition coil that outputs 20 kV. The Ignition coil says on it 12 V and was bought at an auto parts store so I am assuming its an ignition coil for a car. What kind of battery should we...
[SOLVED] Spark transmitter
1. Hello, I am making this project ( a spark transmitter and a receiver), my problem are those coils below ( Lp, La, Lr). How are they connected to the circuit.
three images are attached for the detail
please help me
thanks
Hi,
I am currently working on high voltage system, where I need to create an impluse at the primary side of a potential transformer. I am trying to charge my circuit to at least 10kV using a half wave series voltage mutliper consisting of capacitors and diodes, and discharging them through...
Anyone have a reference or information on longevity and reliability experiments in high power spark gaps?
I am looking at the reliability of a 97GW 78Kamp discharge spark gap I would like to know the erosion factor and fouling rate of different configurations.
Well I used a spark timer and got a spark tape, but forgot how to use the spark tape to calculate time and velocity.
I think its something like the number of dots/60 to get time and v=d/t to get velocity
Am I right?
When two charged metal spheres are brought together (in a Wimshurst machine), a spark occurs at a distance of 1.5cm. An electric field of 30,000V per cm is required to cause a spark. I need to work out the charge on the two balls, assuming (I think) it is equal on both.
I know how to...
Hi all. I recently read an article by a MIT prof. about RLC etc ckts in which he has given a spark plug example. I think the analysis given by him is faulty. The link to the document is here:
http://ocw.mit.edu/NR/rdonlyres/3EBFD5FD-DCF5-422A-A7E3-E1312C74153D/0/trns1_rc_lc_rlc1.pdf
I...
Homework Statement
When an electric train runs,we are familiar to the sparks at the end of cable connections.Why does it occur?Is it due to voltage fluctuations?
Homework Equations
The Attempt at a Solution
Hello All,
I have another set of quick questions that may or may not have a quick answer :smile:. When a simple two-electrode spark gap discharges, what shape do the eclectic and magnetic fields take on? If I were to draw the electric and magnetic field vectors, would they be pointing...
Okay, so I'm building a liquid propulsion rocket, about 4m tall, with a 2000lb trust. The propellants used are liquid oxygen and kerosene. Now the trouble is to find a way to ignite the fuels to start the combustion. Do you guys have any ideas? Thanks!
Dear electrical engineers,
I'm a mechanical engineer and I tried building a capacitance ignition system which didn't work does anybody know what the easiest way is to create a high voltage spark??
My supply voltage is 24 volt.
I just need to press a button and ignite my experiment.
Jaap