@ratul,file transfer speed does not depend on file type assuming no AV is scanning that file type.in your case you most probably created VMWare disk with option "allocate all disk space at once" disabled or your file was too fragmented(which will happen if you do not fix the size of your vmware disk before creating & allocate space all at once).
i don't know what causes this, the size of the VMware machine was dynamic, split to multiple files and totalling ~17GB, all my VMachines are in G:\, which is always defragmented (i defrag whole hdd once a month), though the external HDD isn't defraged...
Same happens while transferring some game files like .bik or .pak or .iso files, in short any sort of file having large volumes of packed data inside them are transferred slower (though rar, zip or 7z files remains unaffected..
)..
To confirm this, i again ran these tests just now, disabling AV, internal HDD defraged while external not, and here are the results:
ISO File:
*i.imgur.com/tuS2K5P.jpg
Video File:
*i.imgur.com/SBY0zNz.jpg
Can you explain this now?? coz i still isn't able to figure out actually what's doing this..