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The force between charges is repulsive between charges with the same sign,
and attractive between charges with opposite signs.
The cathode is charged negative, and the anode is charged positive.
Electrons have a negative charge. So any electron in the neighborhood of a pair
of charged electrodes will be repelled by the cathode and attracted to the anode.
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Is it true that Electrons were discovered when an electric current was passed through gases at low pressures?
Yes, Sir J.J.Thompson did exactly that. ( although at that time the terms used for these phenomena were different). In 1897, Thompson heated a metal to produce cathode rays or electrons. These electrons were attracted towards an anode by providing a potential difference between the two electrodes. Between the cathode and electrode was air at very low pressure which did not stop these cathode rays. Sir Thompson studied these beams in the space between the anode and cathode.
Why cathode rays are negatively charged?
Cathode rays are produced when the metal cathode has a high voltage applied to it - this has the effect of "boiling" the electrons off the cathode's surface producing cathode rays, and so cathode rays can be seen as a stream of electrons i.e. negatively charged particles.AnswerElectrons are released from the surface of a cathode through thermionic emission. This is achieved by a heaterlocated at the cathode, and not due to a high voltage. The function of the high voltage (between the cathode and an anode placed closer to the screen) is to attract these electrons towards the screen of the CRT. So a 'cathode ray' is simply a beam of electrons which, of course, are negatively charged.
Why shape of cathode and anode is like that in electron gun?
The cathode/anode are shaped the way they are to increase the concentration of electrons going in the proper direction. Basically focusing without losing too many.
Why positive rays called canal rays?
Anode Rays are called the canal rays as the cathode used is perforated and the anode rays pass through the holes or canals of The cathode opposite to the anode.
The emission of electrons in high-vacuum tubes is caused by?
The heating by the filament causes the electrons to "boil off". Edison noted this phenomena and it was later picked up by Fleming who used a "grid" which could control the flow of the electrons by introducting a repelling field between the Cathode (heated element that emitted the electrons) and the anode that attracted the free electrons, thus the "Fleming Valve" was invented (the vacuum tube.
Cations are attracted to cathod or anode?
DNA is neither cathode or anode, but it is negatively charged, so the DNA molecules will rn from anode to cathode
Why electrons move from anode to cathode?
The words are all arbitrary - - - BUT electrons have a "negative" charge and are attracted to a positive voltage. (Opposites attract.)
Why flow of current from cathode to anode still the flow of electrons is from cathode to anode?
The direction of current, according to convention, is the direction opposite the direction of electron flow. Remember that the anode is where oxidation occurs, so electrons are lost by the anode. These electrons then move from the anode, to the cathode by a wire that usually connects the two compartments. To reiterate, the electrons flow from the anode (site of oxidation) to the cathode (site of reduction). Because electrons flow from anode to cathode, by convention the direction of current is from cathode to anode (the direction opposite the flow of electrons). Hope this helps!
What is cathode and anode?
cathode is electron negative but anode is positiveAnswerFor electrochemical cells, electrons travel through the external circuit from the anode to the cathode.
What are the uses of Cathode Rays and Anode Rays?
cathode rays can emit electrons anode can collect them
The relationship between a cathode and an anode involves what?
The relationship between a cathode and an anode involves
Where did the electrons from cathode ray come from?
In a cathode ray tube (CRT), the particles, which are electrons, originate at the heated cathode, becoming the so-called cathode rays. The electrons stream off the cathode and rush over to the anode.
What is always true during the operation of a voltaic cell?
The correct answer is Electrons flow away from the anode and also Oxidation occurs at the anode.
What is needed to push the electrons from the cathode to anode?
Actually the electrons are pulled not pushed. The anode attracts them with its positive charge.
Will electrons flow from anode to cathod?
"from anode to cathode". Normally, no. Taking a radio valve (electron tube), since the anode is positive compared to the cathode, and since electrons flow from surplus (at the negative cathode) to deficiency (at the positive anode), they do *not* flow from anode to cathode in normal operation. It's possible to have electrons striking the anode and *knocking off* electrons from it, and then to have those electrons travelling back towards the cathode. This is secondary emission. It was a problem in four-element "tetrode" valves in the early days, but has now been eliminated in practical designs. Long story short: it's possible, but undesirable and not common.
What happens when smaller area is provided to cathode than anode?
When the area provided to the cathode is smaller than the anode the electrons will still flow.
The grid in a high-vacuum triode is usually kept negatively charged with respect to the cathode so that the electrons may be?
A grid in a high-vacuum triode is usually kept negatively charged with respect to the cathode so that the electrons may be passed through to the anode, but controlled by changes in grid voltage. The triode accomplishes this by amplifying signals applied.
