How is current same on both sides of a resistor

In summary, the conversation discusses the concept of current and resistance in an electrical circuit. It is explained that the resistor reduces the rate of flow of electrons and creates a pressure change, similar to a restriction in a water hose. Despite this, the current remains the same on both ends. The presence of resistance inhibits the amount of flow, but it is still true that what goes in must come out.
  • #1
Ayaan
2
0
How come that the current is equal on both the sides.The resistor should decrease the rate of flow of electrons i.e. current.
 
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  • #2
If they weren't the same then you would have a build up of charge inside the resistor.

It's like when water goes in one end of a hose it has to come out the other end.

The resistor reduces the potential of the current. It would be the same as having some restriction inside the water hose. The same water that goes in would come out but it would lose some pressure. The restriction would also slow down the flow of water.

The resistor does decrease the rate of flow. What goes in still has to come out so the current is the same on both ends.
 
  • #3
But I think that the resistor does resist the flow of electrons through it and that is why it gets heated up.
 
  • #4
The usual analogy is water flowing thru a pipe: every drop of water entering a section also leaves that section, even if the size of the pipe changes ... which results in a pressur change. Pressure is analogous to voltage, while water flow is analogous to pressure.

The presence of resistance is thus like a change in pressure.

The analogy isn't perfect, but "what goes in must come out" is valid in both.
 
  • #5
Ayaan said:
But I think that the resistor does resist the flow of electrons through it and that is why it gets heated up.

That is correct and has nothing to do with the fact that what goes in must come out. The resistor inhibits the AMOUNT of flow through it (larger resistors, in ohms, allow less current) but it is still true that however much goes in must come out.
 

1. What is a resistor?

A resistor is an electronic component that is used to limit the flow of electric current in a circuit. It is typically made of a material that has high resistance, such as carbon or metal, and is designed to dissipate heat as current passes through it.

2. How does a resistor work?

A resistor works by creating resistance to the flow of electric current. This resistance is measured in ohms and can be adjusted by changing the material, length, or thickness of the resistor. The higher the resistance, the less current will flow through the circuit.

3. Why is the current the same on both sides of a resistor?

This is because of the principle of conservation of energy. In a closed circuit, energy cannot be created or destroyed, it can only be transferred. Therefore, the current entering one side of the resistor must be equal to the current exiting the other side, otherwise there would be a buildup of energy in the resistor.

4. Can the current change on one side of a resistor?

Yes, the current can change on one side of a resistor depending on the voltage applied to the circuit. Ohm's law states that the current through a resistor is directly proportional to the voltage applied across it. So, if the voltage changes, the current will also change accordingly.

5. What are some practical applications of a resistor?

Resistors have many practical applications in electronics, including voltage division, current limiting, and signal conditioning. They are also used to convert electrical energy into heat, as in the case of electric heaters. Additionally, resistors are used in combination with other components to create various types of electronic circuits, such as filters, amplifiers, and oscillators.

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