Answer:
The value of a physical quantity is expressed by a number followed by some suitable unit.
Explanation:
every measurement of a quantity is an attempt to find true value.
rules for identifying significant figures:
1)All non-zero numbers ARE significant. e.g. The number 33.2 has THREE significant figures because all of the digits present are non-zero.
2)Zeros between two non-zero digits ARE significant. e.g. 2051 has FOUR significant figures. The zero is between 2 and 5.
3)Leading zeros are NOT significant. e.g. The number 0.54 has only TWO significant figures. 0.0032 also has TWO significant figures. All of the zeros are leading.
4)Trailing zeros to the right of the decimal ARE significant. e.g. There are FOUR significant figures in 92.00.
5)Trailing zeros in a whole number with the decimal shown ARE significant. e.g. Placing a decimal at the end of a number is usually not done. By convention, however, this decimal indicates a significant zero. For example, "540." indicates that the trailing zero IS significant; there are THREE significant figures in this value.
