A 550 gram steel block rotates on a steel table (μk = 0.6) while attached to a 1.4 meter long hollow tube. Compressed air fed through the tube and ejected from a nozzle on the back of the block exerts a thrust force of 4.2 Newton perpendiculars to the tube. The maximum tension the tube can withstand without breaking is 50 Newton. If the block starts from rest, obtain how many revolutions does it make before tube breaks?