Time - practice problems

Time (latin tempus) is one of the fundamental physical quantities of SI. The base unit is 1 second. One second is defined as 9,192,631,770 transition oscillations in the Cs-133 atom (the atomic clock ticking). Time cannot be defined using other physical quantities - it is an essential - fundamental quantity. Derived units are minute, hour, day, week, year. For example, 1 minute is defined as 60 seconds. One hour is 3600 seconds. One day is 24 hours. Fractional seconds are 1 ms (millisecond), 1 μs (microsecond), and 1 ns (nanosecond). Frequency is the inverse of the duration of a phenomenon that repeats itself.