https://untitledfinale.wordpress.com/2007/10/09/create-mount-and-copy-floppy-disks-images-under-linux/

Create a disk image from the phisical drive:
cat /dev/fd0 > imagefile.img

Copy image to the phisical drive:
cat imagefile.img > /dev/fd0

Simple isn’t it? And now the fun part :P
If we need it we can create an empty image and mount it using linux’s loop devices.

Creating the image:
$ dd bs=512 count=2880 if=/dev/zero of=imagefile.img
$ mkfs.msdos imagefile.img
   or simplier
Create an empty floppy image of 1.44 MB:
$ /sbin/mkfs.msdos -C /path/imagefile.img 1440



Mounting it:
$ sudo mkdir /media/floppy1/
$ sudo mount -o loop floppy.img /media/floppy1/