Update README.md

experimental_setup/sandbox/Friction_measurment/README.md

@@ -2,16 +2,12 @@
 
 ## Description
 
-This measurement has the purpose to describe the behavior of the mechnical friction of the windtubine.
+This measurement has the purpose to describe the behavior of the mechnical friction of the windtubine (including air friction).
 
 The windturbine is pushed by the motor (at given voltage and current) untilt a steady state is reached.
-After letting the windturbine stabilize, the electricity was switched off.
+After letting the windturbine stabilize, the electricity was switched off and the motor disconnected from th epower supply (open circuit).
 At this point there is no electromagnetic friction, only mechanical friction.
 
-_JPi: There is also friction from the air, I am not sure if your "mechanical friction" includes this._
-
-_JPi: Did you leave the motor connected ot the power supply or you disconnected it?_
-
 The windturbine slows down until it stops.
 
 The angular speed was measured during this process.