I want to measure the voltage across a resistor in my circuit. The circuit is battery powered. I don't want to use the two probe method and calculate A-B to get the results. Can I use one probe to measure the differential voltage as shown in the figure below? No other point in the circuit is connected to the oscilloscope GND except one of the test points.
Looks like you are trying to measure current. A single ended probe would work only work if the resistor was also connected to ground.
Info on low side power measurements: http://www.electronicdesign.com/power/what-s-difference-between-high-side-and-low-side-current-sensing