But producing a phone isn’t instantaneous, it isn’t like the click of the shutter in a high-speed camera. Let’s assume that it takes about 15 minutes (rounded up to 1,000 seconds) to assemble a single iPhone. How many parallel production pipes need to accumulate ten phones a second? 1,000 divided by 1/10 equals…10,000! Ten thousand parallel pipes in order to output ten phones per second.