Answer:
In the computer storage memory, a logical file structure refers to a collection of files which are set-up in an organized way inside different directories, folders/sub-folders and storage volumes. While a physical file structure of a file refers to the physical storage place which are arranged linearly as an address space .
PART B:
It is important not to have application programs interacting directly with the physical file structure because they (Application programs) already have a logical view of the computer's secondary storage, so application programs can have faster maneuvering and access to stored data