Mechanical energy mechanical energy of the colliding objects has been converted into an equal amount of heat. Thus, the total energy of the system remains unchanged though the mechanical energy of the system has reduced. A satellite of mass formula_4 at a distance formula_5 from the centre of Earth possesses both kinetic energy, formula_6, (by virtue of its motion) and gravitational potential energy, formula_7, (by virtue of its position within the Earth’s gravitational field; Earth's mass is formula_8). Hence, mechanical energy formula_9 of a satellite is given by If the satellite is in circular orbit, the energy conservation equation can be further
Feathers: The Evolution of a Natural Miracle murres if they are not on water). He then explains how the structure of feathers is waterproofing, keeping birds dry in wet conditions. Hanson interviews John Sullivan, an experienced fly fisher who explains the role of feathers in fly fishing. Later, Hanson explains the history and use of feathers in quill pens, which he uses as an example of how feathers have been adapted for other purposes beyond their natural evolutionary purposes. Hanson also describes his experience observing the behavior of vultures in Kenya, in which he discusses the lack of feathers on the heads of vultures. Hanson interviews Kimberly