What is time and the SI unit of time second

What is Time?

We know time definitely exists because of our memory and consciousness. For example; you live in a house which you constructed two years back. The place where your house is located was an empty plot before your house was constructed. You remember the order of events happened since you bought that plot till now. Now you know the changes happened to that plot of land as the time moved forward. Definitely time exists, but what is it?

Time can be defined as a measurable dimension of the physical universe that keep the sequence of events in order. Oxford Dictionary defines time as "continued progress of existence and events in the past, present and future regarded as a whole".

During the period of classical physics (before 1900), time and space were considered as two different entities. Space was considered as a stage where events happened in chronological order. But later, Albert Einstein taught us that time and space are not two different things. Time and space are woven together in universe, called as spacetime fabric.

What is the SI unit of time?

The SI units for time is "second". We have 24 hours in a day. One hour is 60 minutes and a minute is made of 60 seconds. Unit of Time, "second" is one of the seven base SI units. second is represented by symbol "s"

We have 24 hours in a day. One hour is 60 minutes and a minute being 60 seconds.

So, a day consists of 24 * 60 * 60 = 86400 seconds. A second is 1/86400 of a day.