Why did the solar nebula heat up as it collapsed?
A) Nuclear fusion occurring in the core of the protosun produced energy that heated the nebula.
B) As the cloud shrank, its gravitational potential energy was converted to thermal energy.
C) Radiation from other nearby stars that had formed earlier heated the nebula.
D) The shock wave from a nearby supernova heated the gas.
E) Collisions among planetesimals generated friction and heat.

Question

Quizplus · Accepted Answer

As the solar nebula collapsed, its gravitational potential energy was converted to thermal energy, causing it to heat up. This is a fundamental principle of thermodynamics known as the conservation of energy. As particles move closer together, their kinetic energy increases, which in turn increases their temperature. This process continued as the nebula collapsed and ultimately formed the protosun and the planets.

Why Did the Solar Nebula Heat Up as It Collapsed