They are scientifically different althouhg they seems to be same. `2.0 m` has two significant figures, and hence its precision is 0.1 part in 2, i.e, 50 ppt (part per thousand). `2.00 m` has three significant figures and its precision is 0.01 parts in 2, i.e., 5 ppt. Hence, `2.00 m` is more precise measurement than `2.0 m`.
