▁and ▁allows ▁for ▁much ▁quick er ▁flash ▁rates , ▁but ▁dr ast ically ▁reduces ▁the ▁lifetime ▁of ▁the ▁flash ▁t ube ▁if ▁power ed ▁for ▁significant ▁periods ▁of ▁time . ▁Such ▁stro bes ▁require ▁a ▁form ▁of ▁current ▁limit ing , ▁without ▁which ▁the ▁flash ▁t ube ▁would ▁attempt ▁to ▁draw ▁high ▁curr ents ▁from ▁the ▁electric ity ▁source , ▁potentially ▁tri pping ▁elect rical ▁break ers ▁or ▁causing ▁voltage ▁dro ps ▁in ▁the ▁power ▁supply ▁line . ▁ ▁Ind ividual ▁stro be ▁flash es ▁typically ▁only ▁last ▁around ▁ 2 0 0 ▁micro seconds , ▁but ▁can ▁be ▁sust ained ▁for ▁greater ▁or ▁less er ▁periods ▁of ▁time ▁depending ▁on ▁the ▁stro be ' s ▁intended ▁use . ▁Some ▁stro bes ▁even ▁offer ▁continuous ▁mode ▁of ▁operation ▁where by ▁the ▁arc ▁is ▁sust ained , ▁providing ▁extremely ▁high ▁intensity ▁light , ▁but ▁usually ▁only ▁for ▁small ▁amounts ▁of ▁time ▁to ▁prevent ▁over he ating ▁and ▁event ual ▁break age ▁of ▁the ▁flash ▁t ube . ▁ ▁App lications ▁ ▁St rob os cop ic ▁effect ▁▁ ▁Special ▁cal ibr ated ▁stro be ▁lights , ▁capable ▁of ▁flash ing ▁up ▁to ▁hundreds ▁of ▁times ▁per ▁second , ▁are ▁used ▁in ▁industry ▁to ▁stop ▁the ▁appearance ▁of ▁motion ▁of ▁rot ating ▁and ▁other ▁repet it ively ▁operating ▁mach in ery ▁and ▁to ▁measure , ▁or ▁adjust , ▁the ▁rotation ▁spe eds ▁or ▁cycle ▁times . ▁Since ▁this ▁stop ▁is ▁only ▁apparent , ▁a ▁marked ▁point ▁on ▁the ▁rot ating ▁body ▁will ▁either ▁appear ▁to