Dipole model of the Earth's magnetic field (MLAT), or geomagnetic latitude, formula_10 is measured northwards from the equator (analogous to geographic latitude) and is related to formula_9 by formula_12. In this case, the radial and azimuthal components of the magnetic field (the latter still in the formula_9 direction, measured from the axis of the north pole) are given by formula_14 formula_15 formula_16 where formula_17 in this case has units of Earth radii (formula_18). Invariant latitude is a parameter that describes where a particular magnetic field line touches the surface of the Earth. It is given by formula_19 or formula_20 where formula_21 is the invariant latitude and formula_22
Latitude ON a customizable, Linux-based Mobile Internet Device (MID) platform the laptop is able to boot almost instantly and view Email, document reader, calendar, contacts and access the Internet. First laptop models to include Latitude ON were E4200 and E4300 released in February 2009. Last laptop model introduced so far is Latitude Z600. Dell claims that battery life can be extended to days. Latitude ON Reader is similar to Dell's MediaDirect where the software is located in a separate partition on the system hard drive and has a dedicated button to power on. There are several versions of Latitude ON: Latitude ON