Final answer:
Correct option: (c) The orbital radius will decrease.
Resistance from cosmic dust causes a satellite in orbit to lose kinetic energy and move into a lower orbit, ultimately falling towards Earth due to decreasing altitude and increasing gravitational pull.
Step-by-step explanation:
If a satellite revolving in a circular orbit experiences resistance due to cosmic dust, it will not move to a higher orbit. Instead, the orbital radius will decrease because the satellite loses kinetic energy due to the resistance. As kinetic energy is lost, the satellite slows down, and its altitude decreases. Consequently, according to physics principles, this will cause the satellite to eventually fall towards the Earth as its orbit decays.
Considering conservation of angular momentum and energy, an object in a lower orbit moves faster because it has less potential energy but more kinetic energy. Therefore, as a satellite spirals inward due to resistance, such as atmospheric drag or, in this case, cosmic dust, its orbital speed increases. This occurs because the gravitational pull gets stronger as the satellite gets closer to the Earth, increasing its velocity.