One of the easiest ways to view the EXIF information of a JPEG file is to use the default image viewer. This tool in Ubuntu is the Eye of GNOME, also simply called the GNOME Image Viewer.
To view the EXIF information, just open the image in Eye of GNOME and choose Image > Properties > Details. This shows all the EXIF tags and their values in the JPEG file.
Tried with: Eye of GNOME 3.4.2 and Ubuntu 12.04 LTS