A unit of time or time unit is any particular time interval, used as a standard way of measuring or expressing duration. The base unit of time in the International System of Units (SI), and by extension most of the Western world, is the second, defined as about 9 billion oscillations of the caesium atom.
Also to know is, what are some ways that we measure time?
Measuring time by the Sun, the Moon and the Stars. As the sun moves across the sky, shadows change in direction and length, so a simple sundial can measure the length of a day. It was quickly noticed that the length of the day varies at different times of the year.
What are the instruments used to measure length?
Length is the measurement of distance.There are many tools such as vernier calliper,gauge,tapes,metric rulers which are used to measure length. Depending upon what we tend to measure,tool varies. Vernier calliper is used to measure the length of rod, length & diameter of a wire.