Strain gage to measure drag in a wind tunnel?

[gsjbjt]

How would a strain gage be set up (on top of the model? around the sting?) to measure drag? I don't quite understand the connection between the force of drag and some sort of compression/tension force...?

Thanks for the clarification.

 

[Simon Bridge]

Consider: what is drag? Where does it come from?

 

[Aero51]

Think of a bending beam...