Physics Class 9th
Chapter No 01
Physical Quantities and Measurements.
Answer
Prefixes : prefixes are words or letters that are added before SI unit.
Or
A Mechanism through which a term in scientific notation is expressed by giving a proper name to its power of 10 is called prefix to the power of ten. Power of ten is called prefix.
Explaination: prefixes makes standard form to be written even more easily.
Examples and Symbols: