Measurement of Time
Time is defined as an interval between two successive events. The unit of time is the second and other units may be minutes, day, hour, week, month, or year.
60 seconds = 1 minute
60 minutes = 1 hour
24 hours = 1 day
Any device that can repeat its motion regularly and constantly can be used to measure time.
In the laboratory, a stop-watch, or a stop-clock is normally used to measure time and it has an accuracy of 0.1 seconds.