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nuby
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Do electrons flowing in a circuit perform work with their mass (or kinetic energy)? For example like a water flowing in a creek through a turbine. If so does E = 1/2 mv^2 apply.
The kinetic energy of a non-relativistic electro, such as those in an electric circuit, is K = mv^2/2. A deeper analysis requires quantum mechanics where the concept of force, and thus work, is meaningless.nuby said:Do electrons flowing in a circuit perform work with their mass (or kinetic energy)? For example like a water flowing in a creek through a turbine. If so does E = 1/2 mv^2 apply.
Division. E.g. the expression x/2 means that x is divided by two.nuby said:What does the "/2" represent in that equation (in reality)? K = mv^2/2
Thanks for your response.
First, there is no such thing as a unipolar magnet.nuby said:If you have two magets sitting on a table (N/S), with say a unipolar magnet between them (o), and a non-magnetic barrier (I).
like this:
..N<...I...o...<S..
From a simple point of view, the mass of the 'o' will be the main factor of the work actually done. I believe this is the same concept that is occurring in most electronic circuits.
Correct. An object with 1kg mass will end with a velocity of 1.41 m/s and an object with 2kg mass will end with a velocity of 1 m/s, but the work is 1J in each case and the KE is also 1J in each case.nuby said:So if you throw an object in space, and it travels 1M at 1N force, is the work still 1J regardless of the mass?
DaleSpam said:Correct. An object with 1kg mass will end with a velocity of 1.41 m/s and an object with 2kg mass will end with a velocity of 1 m/s, but the work is 1J in each case and the KE is also 1J in each case.
Do electrons flowing in a circuit perform work with their mass (or kinetic energy)?
W = f.dnuby said:Can you give me the simple equation for that, as well as the equation for energy required to slow down that same object?
Yes. However, remember that in most circuits (other than cathode rays etc. as mentioned), the electrons never move with any significant velocity, never attain any appreciable amount of KE, and give up any energy imparted to them almost as soon as they get it.nuby said:Can KE = 1/2mv^2 and F=ma or be applied to electrons.
nuby said:I've heard electrons travel very slowly in standard circuits before (cms per hour), however, I've never seen any proof of this. How was this measurement taken?
The units aren't quite right for that, also voltage is a scalar and force is a vector. Do you know what the gradient of a scalar field is? The E-field is the gradient of the voltage. So what I would say is "the E-field is the field that moves electrons, similar to the gravitational field, a field that moves mass". In this manner the voltage is similar to the height, a measure of the potential energy in the mass or charge and only indirectly related to the force on a mass or charge.nuby said:Couldn't voltage be considered a force that moves electrons, similar to Newtons, a force that moves mass.
zarbanx said:the work done by electrons in a circuit is through change in its potential.the current in the circuit can be viewed as a stream of positive charges moving from +ive plate to -ive plate.thus when these +ive charges pass through the wire(a non ideal wire which has resistance) there is a fall in potential of the +ive charges and it is this energy tht reappears as heat energy.
i hope it was of some help. i really could not get wht u want to know so i wrote wht i know tell me if it was of any help or not
marmoset said:About the integral explanation of the 1/2 in the expression for kinetic energy, I understand the integration, but why does integrating mass x velocity with respect to velocity give kinetic energy?
I had always explained the half by saying that to stop an object mass m traveling at a velocity u, you apply a force which gives the object an acceleration of -F/m. Then I use v2 = u2 + 2as to work out the distance (s) this object travels before it stops. So 0 = u2 - 2Fs/m, and so Fs = mu2/2. Fs expresses the work done to stop the object, and so from conservation of energy the object's initial KE must have beeen mu2/2.
Electrons flow in a circuit from the negative terminal of a power source, through the conductors, and back to the positive terminal of the power source. This flow of electrons is known as an electric current.
Electrons carry energy from the power source to the components in a circuit, allowing them to perform work. This work can include powering light bulbs, turning on motors, or producing sound in speakers.
Electrons transfer energy by colliding with atoms in the conductors of a circuit. These collisions cause the atoms to vibrate, which produces heat and light energy. The electrons then continue to flow, transferring energy to other components in the circuit.
Yes, electrons can perform work in both series and parallel circuits. In a series circuit, the electrons flow through each component in a single path, while in a parallel circuit, the electrons split into multiple paths and flow through each component simultaneously.
Voltage is the force that pushes electrons through a circuit, while current is the rate of flow of electrons. The higher the voltage, the greater the force pushing the electrons and the higher the current. However, the flow of electrons is also affected by the resistance of the circuit, which can limit the current flow.