Stopwatch in physics definition
A stopwatch is used to measure the time interval of an event.
Types of stopwatch
- Digital stopwatch
- Mechanical stopwatch
Digital stop watch
It is commonly used in laboratories,it can measure a time interval up to 0.01 second.It starts to indicate the time lapsed as the start/stop button is pressed.As soon as start/stop button is pressed again,it stops and indicates the time interval recorded by it between start and stop of an event.A reset button restores its initial zero setting.
A mechanical stop watch can measure a time interval up to 0.1 second.It has a knob that is used to wind the spring that powers the watch.It can also be used as a start stop and reset button.The watch starts when the knob is is pressed once.When pressed second time,it stops the watch while the third press brings the needle back to zero.