Always use your name for store id. It's most convenient. whenever you have some problems with product, they will ask you for id. So, its better to use real name. I often use some fictitious characters like Peter Parker, Ken Adams, etcetera while signing up on some timepass websites.
The gravitational potential energy near a planet is then negative, since gravity does positive work as the mass approaches. This negative potential is indicative of a bound state; once a mass is near a large body, it is trapped until something can provide enough energy to allow it to escape.
Energy can be kinetic energy or potential energy. Kinetic energy is the energy a mass has because it is moving. Potential energy in an object, in matter, in a charge or other situation has the ability to perform work or to be converted into kinetic energy or a different kind of potential energy.