A molecular cloud is a cold, dense nebula of gas and dust in space. Under certain conditions, gravitational instability can cause the cloud to collapse, leading to star formation.
State the name of the fundamental force responsible for this initial collapse.
A giant molecular cloud, Nebula K\text{K}K, is modelled as a sphere of gas and dust particles with a diameter of 5.4 pc5.4\text{ pc}5.4 pc.
The nebula has a particle density of 2.4 × 1013 gas and dust particles per m3\text{m}^3m3 and is at a temperature of 85 K. The gas within the nebula behaves as an ideal gas.
Show that the volume of Nebula K\text{K}K is approximately 2.5 × 1051 m3.
(1 pc=3.1×1016 m1\text{ pc} = 3.1 \times 10^{16}\text{ m}1 pc=3.1×1016 m)
Calculate the total kinetic energy EkE_{\text{k}}Ek of the gas and dust particles in Nebula K\text{K}K.
Another nearby nebula, Nebula L\text{L}L, has a diameter of 3.2 pc3.2\text{ pc}3.2 pc and possesses a similar composition and density to Nebula K\text{K}K.
Calculate the ratio
mass of Nebula Kmass of Nebula L \frac{\text{mass of Nebula K}}{\text{mass of Nebula L}} mass of Nebula Lmass of Nebula KAfter a long period of stellar evolution, Nebula L\text{L}L will collapse to form a main sequence star with a mass similar to that of our Sun. Describe the eventual evolution of this low-mass star after it leaves the main sequence.
