Smiple circuit with just one resistor

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In a simple circuit with one resistor, increasing the supply voltage results in a higher current flow, as dictated by Ohm's Law, which states that current is directly proportional to voltage and inversely proportional to resistance. Even at low voltage, some current can still flow, as the resistor always offers resistance. Increasing voltage provides more energy per coulomb, allowing charge to move more effectively through the resistor. The resistance itself remains constant, meaning it does not become harder for charge to flow as voltage increases. Ultimately, higher voltage leads to increased current and energy dissipation in the circuit.
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In a smiple circuit with just one resistor, consider the current that flows. If you increase the resistance, less current flows. If you increase the supply voltage, the current increases.
One book says that increasing voltage provides charge with the energy needed to get through the resistor, but even when the supply voltage is very low, some charge still gets through doesn't it, just not very much.
So increasing the voltage does increase the energy per coulomb, but this can't be the reason why more current flows can it, because the charge can get through even when it has a low energy?
The only think i could think of is that a higher voltage makes the charge circulate faster due to the higher potential difference, but that sounds a bit wrong.
Can anyone help me out please? Basically i just want to know how come increasing voltage increases the current? And how come when you increase the voltage, more energy is dissipated for a given resistance? Because it can't suddenly become harder for charge to get through a resistor when you inrease the supply voltage can it?
 
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Think of a garden hose. Blow into it with your mouth. The pressure with which you blow is analogous to voltage. More pressure->more flow and also more energy dissipated.
One book says that increasing voltage provides charge with the energy needed to get through the resistor
This implies you need a minimum energy to get through the resistor. That's wrong. A resistor is not a threshold device. Either the book is wrong or you paraphrased it incorrectly.
So increasing the voltage does increase the energy per coulomb
That's absolutely right. It's the definition of voltage.
 


Increasing the voltage in a simple circuit with just one resistor does indeed increase the amount of current flowing through the circuit. This is due to Ohm's Law, which states that the current through a conductor is directly proportional to the voltage applied and inversely proportional to the resistance of the conductor. In other words, as the voltage increases, the current increases proportionally, and as the resistance increases, the current decreases proportionally.

You are correct in thinking that increasing the voltage provides the charge with more energy to get through the resistor. However, even when the supply voltage is very low, some charge will still be able to flow through the circuit. This is because the resistor still offers some resistance to the flow of current, no matter how low the voltage is.

The reason why increasing the voltage results in more energy being dissipated for a given resistance is because the voltage is the driving force behind the flow of current. When the voltage is increased, more energy is available to push the charge through the circuit, resulting in a higher current. This higher current means that more charge is flowing through the resistor per unit time, leading to more energy being dissipated.

To answer your question about why it can't suddenly become harder for charge to get through a resistor when you increase the supply voltage, the key thing to remember is that the resistance of a resistor is a constant value. It does not change with the supply voltage. So, while increasing the voltage may make it easier for charge to flow through the resistor, the resistance remains the same.

In conclusion, increasing the supply voltage in a simple circuit with just one resistor results in more current flowing through the circuit due to Ohm's Law. This increased current also leads to more energy being dissipated for a given resistance.
 
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