Internal resistance understanding

AI Thread Summary
Internal resistance in components, particularly batteries, impacts the current flow by reducing the effective voltage available at the terminals, known as terminal potential difference (pd). The terminal pd can be calculated by subtracting the voltage drop across the internal resistance from the electromotive force (emf) of the battery. Key formulas include Ohm's Law (V = IR), the relationship between emf, terminal pd, and internal resistance (emf = terminal pd + I * internal resistance), and the power equation (P = IV). Understanding these concepts is crucial for analyzing circuit behavior and efficiency. Mastering these formulas will aid in calculating resistance, voltage, pd, emf, and current effectively.
waterliyl
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Hello,
I'm having difficulty trying to understand internal resistance of any component. I don't understand how exactly the internal resistance affects the current and what exactly is the terminal pd?

And for calculating resistance, voltage, pd, emf, current and all those basic things - what are the basic formulas that could help?

Thanks,
Aakeen
 
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waterliyl said:
I don't understand how exactly the internal resistance affects the current and what exactly is the terminal pd?
Start here: Battery With Internal Resistance
 
Thank you!
 
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