Question

Explain unit of time. Write the principal of periodic motion​

Answer 1

A unit of time or midst 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.

There is no specific Principal of periodic motion.



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Answer 2

Answer:

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. There is no specific Principal of periodic motion. Hope it helps...