A resistor is a two-terminal electronic component

[Jin S Zhang]

This is definition of resistor from Wikipedia.

1. " A resistor is a two-terminal electronic component that opposes an electric current by producing a voltage drop between its terminals in proportion to the current"

And this is another mention about Ohm's Law from a diagram of Wikipedia.

2. "A voltage source, V, drives an electric current, I , through resistor, R, the three quantities obeying Ohm's law: V = IR."


After reading these two statements, I got confused. From 1, I can assume that a resistor produces a voltage V to oppose an electric current. But, when I read 2, Voltage send current through resistor not produced by resistor. Could you please explain me about that. I just started learning Electricity. Thanks.

 

[BryanP]

The statements just tells you that since R is fixed, the voltage has to drop in proportion to the current passing through it.

You're basically driving a current with a certain voltage. Once you pass that current through resistor element R, it's going to oppose the current (the IR part), but because I is directly proportional to V (Ohm's Law V = IR), if you cause a drop in current using resistor R, then the voltage has to drop. Therefore, that is why you have a voltage drop after you pass through R.

 

[oswaler]

Hello! I can help clarify the confusion you have about resistors and Ohm's Law. Let's break down the statements you mentioned.

Statement 1: "A resistor is a two-terminal electronic component that opposes an electric current by producing a voltage drop between its terminals in proportion to the current."

This statement is accurately describing the function of a resistor. A resistor is designed to resist the flow of electric current, which means it reduces the amount of current passing through it. This resistance results in a voltage drop across the resistor, which is proportional to the current passing through it. In other words, the more current that passes through the resistor, the higher the voltage drop will be.

Statement 2: "A voltage source, V, drives an electric current, I , through resistor, R, the three quantities obeying Ohm's law: V = IR."

This statement is describing the relationship between voltage, current, and resistance, known as Ohm's Law. Ohm's Law states that the voltage (V) across a resistor is equal to the current (I) passing through it multiplied by the resistance (R) of the resistor. In simple terms, it means that the voltage and current in a circuit are directly proportional to each other, and the resistance of the circuit determines this relationship.

To address your confusion, it's essential to understand that a resistor does not produce voltage. It resists the flow of current, which results in a voltage drop. The voltage source, such as a battery, provides the initial voltage that drives the current through the resistor. The resistor then reduces the current and produces a voltage drop in proportion to the current. This relationship is described by Ohm's Law.

I hope this helps clarify the concept of resistors and Ohm's Law for you. Keep learning and exploring the world of electricity!