Length And Its Measurements

Length:
 

"The distance between two fixed points is known as Length."
 

 

➡SI unit of length is metre
 

                                                    Measurements
 

➡Light year:
 

➡Distance travelled by light in one year is known as light year.
 

➡One light year is equal to 9.46 x 10¹⁵ m.

➡Astronomical unit( A.U):
 

➡The distance between the Earth and the Sun is known as astronomical unit.
 

➡One astronomical unit is equal to 1.496 x 10 ^ 11 metre
 

➡Parallactic second( parsec):
 

➡Parallactic Second is the biggest unit of distance.
 

➡It is equal to 3.26 times of the light year.
 

➡1 parsec is equals to 3.08 x 10 ^ 16 m
 

➡Femtometer( Fermi):
 

➡Femtometer is the smallest unit of distance.
 

➡1 Fermi is equals to 10 ^ - 15 m
 

➡Least count:
 

➡Least count is the smallest quantity that can be measured accurately.
 

➡Least count is equal to 1 mm( on regular scale).
 

➡Curved object:
 

➡Length of a curved object is measured using a thread, then this thread is spread along the side of a regular measuring  scale.