Question

A battery is labeled with a voltage of 9 volts. When the battery is connected to a resistor, the current is 1.2 amp and a digital voltmeter placed across the battery measures 8.0 volts. What is the internal resistance of the battery?

Answer 1

0.833 ohm

Step-by-step explanation:

We have given the labeled voltage that is terminal voltage V =9 volt

The current through the battery is 1.2 A

The emf of the battery that is E =8 volt

For any battery we know that
`V=E+iR`

Where V is terminal voltage , E is EMF and R is internal resistance

So
`9=8+1.2* R`

`R=(1)/(1.2)=0.833ohm`