POTD: Speed #2

Speed #2 Budapest, Hungary 2011

Here’s a challenge for the engineer/scientist types out there. Given the exposure for this photograph was 1/20s, estimate the speed this bicyclist was traveling. My first calculation was 82mph. I think I need to go back and revisit my assumptions. In the meantime, Happy New Year!


2 thoughts on “POTD: Speed #2”

  1. Assuming the leading blur on the curbside object nearest the biker is about 1 foot, the biker travels —
    1 foot in 1/20 second = 20 ft/sec.
    20 ft x 60 seconds = 1,200 ft/minute
    1,200 ft x 60 min = 72,000 ft/hour
    72,000 ft / 1 Mile (5,280 ft) = 13.636 mph
    But, I’m no engineer so WDIK?
    Hoppy Gnu Ear !

    1. Jim, I assumed the blur was 6s, and used the same calculation process as you did. So, once I corrected the error that gave me 80mph as the result, it’s not surprising I got half the speed you did.

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