Measurement of Time

Measurement of time

                         We perform many activities in our day-to-day life. Many events take place, but duration of each event differs.

                Time is defined as the interval between two events. The SI unit of time is second

                For measuring time we use pendulum clock, wrist watch,  wall clock, stop clock etc. In olden days people used sundial, sand clock, water clock etc. For measuring time accurately now a days we use electronic clock and atomic clock.

Multiples and sub multiples of time: Time interval larger than 1 second is expressed in minute, hour, day, week, month, year etc. These are called multiples of time. Any time interval less than 1 second is expressed in millisecond, microsecond etc. these are called sub multiples of time

Physical quantity          SI unit           Multiples         Sub multiples

         time                      second            minute            millisecond

                                                             hour                microsecond

                                                             day

                                                             week

                                                             month

                                                             year

1 minute  = 60 second

1 hour      = 60 minute

1 day        = 24hour

1 year       = 365 1/4 days

1 second   = 1000 millisecond

1 second   = 1000000 microsecond