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 the byways of evolution and the wonderful world of birds." "Scientific American" published an online review of "Feathers" in their blog "Tetrapod Zoology" by Darren Naish. Naish commented that prior to Hanson's book, "it doesn’t seem that any one book has ever been devoted to feathers and feathers alone. ... "Feathers" is thus a rather significant book, and very nice it is too." Naish also stated that ""Feathers" is not the provincial view of someone only interested in ecology or conservation biology; on the contrary, this is a remarkably well-rounded review of the subject." In a review published in the