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What is internal resistance
The electrons colliding with the ions in the battery
What is external or load resistance
The total resistance of all the components in the external circuit.
What does E.M.F stand for
Electromotive force
What is E.M.F
The total amount of work the battery does on each coulomb of charge
What is the terminal potential difference
The potential difference across the load resistance
What is lost volts
The energy wasted per coulomb overcoming internal resistance.
What is an equation for lost volts
E.M.F = terminal potential difference + lost volts
How do you calculate the total E.M.F in a series circuit
Add them together
How do you calculate the total E.M.F in a parallel circuit
The E.M.F is equal to whichever branch it passes through. So if each cell has the same E.M.F it does not change.
How do you get the internal resistance from a practical
Have a variable resistor on it’s highest resistance and record the potential difference and current across it. Repeat with lower values of resistance. Plot an I-V graph and calculate the gradient. Then multiply by -1.
How is the equation rearranged in a practical to find internal resistance graphically
V = -r (I) + E.M.F
