Measuring the Internal Resistance of a Battery - Mini Lab Experiment

0:00 Introduction
0:20 Terminal Voltage Definition
0:43 EMF
1:00 Internal Resistance
1:37 Equations
2:48 Demonstration
4:04 Experiment Apparatus
6:48 Experiment Data
8:08 Graph to determine Internal Resistance
9:06 Data for each experiment

Worksheet:
Some of the questions this video will investigate are the following:
1. What exactly is the Internal Resistance of a battery?
2. How are the quantities of Terminal Voltage, Electromotive Force and Internal resistance connected?
3. What would a typical experiment to measure Internal Resistance for a standard commercial battery look like (what equipment would be needed)?
4. How a graph could be used to calculate Internal Resistance when current and terminal voltage are measured?

This video will show you an experiment that can be used to measure the internal resistance of a battery, by measuring voltage and current in a circuit. The resistance of the circuit can be altered with the use of a variable resistor.

This experiment is performed with 10 different batteries in total. For each battery, about 5 or 6 different data points (voltage and current) are measured. With the data, a calculation can be completed to measure the internal resistance.