Question

In: Physics

Isolated molecular clouds can have a temperature as low as 20 K and a particle density...

Isolated molecular clouds can have a temperature as low as 20 K and a particle density as great as 1.2×10⁵ per cubic centimeter.

What is the minimum mass that a cloud with these properties needs in order to form a star?

Mcloud= _________ MSun

Expert Solution

GIVEN:

The temperature of the molecular clouds,

The number of particles per unit volume,

TO FIND the minimum mass that a cloud with these properties needs in order to form a star

ASSUMPTION: The molecular cloud is assumed to be entirely made up of Hydrogen.

APPROACH:

The minimum mass of stability is often called as Jean's mass . It is a critical mass for the star formation, if the cloud collapses under its own gravity and if there is not sufficient gravity to support the pressure and the cloud may fragment.

This Jean mass is given as

here is the boltzmann constant,

is the universal gravitational constant

is the mass of the hydrogen atom

is the temperature of the molecular cloud

is the number of hydrogen atoms per unit volume.

Substituting the corresponding values of the constant we get,

This is the minimum mass of the cloud that could form a star.

The mass of the sun is ,

Therefore, the mass of the cloud

genius_generous answered 1 year ago

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