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What kind energy of electrons is lost when current passes through a resistor?

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What happens to electrons when they pass through a resistor? Does current decrease when its passes through a resistor? Does voltage also decrease???

Austin Rojers
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What kind energy of electrons is lost when current passes through a resistor?

Electrons leave the resistor with less potential energy than they enter the resistor with (the electric potential at the exit terminal is more positive than than that at the entry terminal, and electrons have negative electric charge).

Yes, electrons give up kinetic energy to the lattice that makes up the resistor due to collisions. This is why the resistor is heated by the electron current through.

However, there is also an electric field through the resistor (there must if there is a potential difference across the resistor terminals). So, while the electrons give up energy (on average) due to collisions with the lattice, they also gain kinetic energy as they are accelerated by the electric field inside.

On the whole, the kinetic energy lost to the lattice is balanced by the gain in kinetic energy due to the electric field, so the energy delivered to the resistor lattice is balanced by the potential energy lost by the electrons.

Alfred Centauri
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As the electrons are in motion they have kinetic energy. When these electrons pass through resistor the kinetic energy of the electrons is converted into the heat energy and it is then said that the energy is consumed.

Because kinetic energy is being lost in the resistor the rate at which the electron flows decreases and its said that current is decreased because of the resistor.

And because the flow of electrons through the resistor will lose kinetic energy there will also be the voltage drop across the resistor.

Alex
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    Alex, I've downvoted your answer because, on my view, it is more harmful than helpful. (1) Current isn't necessarily decreased by a resistor - consider the elementary case of a resistor connected to a constant current source. (2) The voltage drop across the resistor is due to the changing charge density through the resistor, i.e., the electron density is greater at the entry terminal that at the exit terminal. This (in steady state) is the origin of the electric field through the resistor that in turn gives rise to the voltage across the terminals of the resistor. – Alfred Centauri Apr 09 '20 at 01:00