91Ó°ÊÓ

Terminal voltage is equal to the difference between the battery voltage and voltage drop across the internal resistance. Determine the current through the load is$i$, internal resistance of the battery is rand emf is$V$, then using Ohm’s law,determine the relationship between$V_T$and i. Plot the given data would give us the value of emf of the battery as well as internal resistance using the graphing calculator and linear regression fit.

Formula:

$V=ir$

All the current through the load would pass through the internal resistance of the battery. if we know the terminal voltage $V_T$,the current through the load as i and internal resistance of the battery with emf V . The required equation is:

$V_T=V−ir$ (1)

the least square fit method for the $V_T$against i values given to us, we can write

$V_T=13.6107-0.05985i$ (2)

Compare equation (1) and (2), determine the emf of the battery is$13.6107\text{ V}$.

Therefore,$V≈13.6V$

Compare equation (1) and (2), we can conclude that internal resistance as follows:

$\begin{array}{c}r=0.05985\mathrm{Î\copyright }\\ ≈0.060\mathrm{Î\copyright }\end{array}$

Determine the plot for the given condition as: