Measuring voltage drop across 10 ohm, 100 ohm and 10 kilohm resistors (one at a time) - very simple circuit

Below is a picture of my very simple circuit. There are three resistors 10 ohm, 100 ohm, and 10 kilohm. I connect them one at a time in serial fashion and measure voltage drop across them. When I measure battery voltage I get 6.5 Volt and this is what I expect as voltage drop on all of my measurements, but here is what I get:

1. When I measure voltage drop across 10 ohm resistor I get 0.2 volt.
2. When I measure voltage drop across 100 ohm resistor I get 1.0 volt.
3. When I measure voltage drop across 10 kilohm resistor I get 5.8 volt.

Why do I get all these different readings and not something around 6.5 Volt?

P.S. On the image the circuit is not closed, but this is how I took picture, circuit is closed on all measurements.

• this question has been asked here a lot ... the rest of the voltage is dropped across the battery internal resistance ... |l------\/\/\-----\/\/\----- Apr 2 '21 at 21:50
• Pay attention not to fry the 10 Ohm resistor when using a fresh battery. Apr 3 '21 at 5:44
• @tobalt, I already saw it smoking ;-). How do I decide what current resistor can withstand? Apr 3 '21 at 13:34
• In this simple circuit, the worst case power in the resistor will be 81/R Watts. The resistor are probably rated for 0.25 W... The real power will be less because of internal Resistance in the battery but don't go grossly over this limit. Apr 3 '21 at 14:17

A fresh Panasonic alkaline battery (consumer grade, not industrial) has an internal resistance of less than 4$$\\Omega\$$. 