High School

A 9.0-volt battery is connected across 2.2 kilo-ohm and 6.8 kilo-ohm resistors connected in series.

(a) Calculate the potential difference across the 2.2 kilo-ohm resistor.

(b) Calculate the potential difference across the 6.8 kilo-ohm resistor.

Answer :

Answer:

2.2V; 6.8V

Explanation:

That's a classic voltage divider. The voltage drop across the [tex]2.2 k\Omega[/tex] is [tex]V_{2.2} = {{2.2} \over {2.2+6.8}} 9V = 2.2V[/tex]. The drop across the second resistor is what's left, or [tex]6.8V[/tex]

Else, the two resistors behave like a single resistor of [tex]9k\Omega[/tex] (the sum of the two, since it's a series). It means that across them flows a 1mA current (Ohm first law), from which you can calculate the drop across each resistor by multiplying the current by each resistence.