How Does Load Current Influence the Voltage Across a Battery's Terminals?

AI Thread Summary
Load current affects the potential difference across a battery's terminals by causing a decrease in terminal voltage as current increases, due to the internal resistance of real cells. In an ideal power source, terminal voltage remains constant regardless of load current, but this is not the case in practical applications. The discussion emphasizes the need for a physics explanation that accounts for the behavior of real cells, particularly the role of internal resistance. Ohm's Law is relevant for understanding the relationship between voltage, current, and power in this context. Ultimately, recognizing the distinction between ideal and real cells is crucial for accurately addressing the question.
Cici2017

Homework Statement


Please provide a physics explanation of this question:
How does load current affect the potential difference across the terminals of a cell?

Homework Equations

The Attempt at a Solution


p.d. inversely proportional to current. Thus, when I increase, the p.d. decrease and vice versa

Is this a good enough 'physics explanation' for this question? Thanks~
 
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Cici2017 said:
Is this a good enough 'physics explanation' for this question? Thanks~
No, it is not because in an ideal power source it is not true so you need to explain why it IS true (and preferably also to what extent it is true) in a real power source.
 
phinds said:
No, it is not because in an ideal power source it is not true so you need to explain why it IS true (and preferably also to what extent it is true) in a real power source.
I don't know why is it true... :sorry:
 
An ideal cell maintains terminal voltage independent of load current . In a real cell the terminal voltage drops as load current increases .

What common electrical component could you put in series with an ideal cell so that the ideal cell and the additional component together behave like a real cell ?

Edit : Haven't you essentially got the answer to this question in your previous posting?

https://www.physicsforums.com/threads/internal-resistance-of-a-cell.921160/
 
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Voltage times current gives power, but to answer this question, you'll need Ohm's Law.
 
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