Because it is so large. Density is a function of mass/volume.
The density of Betelgeuse is extremely low: 1,119.10 ex.-8 from the density of the sun.
Betelgeuse has a density of about 1.119 × 10−8 that of our Sun. See related question
Yes: Betelgeuse is a semiregular variable star so it is classed as a pulsating star.
Betelgeuse is one of the larger stars, while Barnard's star is just a little red dwarf star. So, yes- Betelgeuse is far larger than Barnard's.
Betelgeuse is about 1,180 times larger the Sun. So Betelgeuse is about 128,620 times bigger than Earth. So as a rough approximation about 2,127,774,087,928,000 Earths could fit into Betelgeuse. That's 2 quadrillion.
The density of Betelgeuse is extremely low: 1,119.10 ex.-8 from the density of the sun.
Betelgeuse has a density of about 1.119 × 10−8 that of our Sun. See related question
Yes, hydrogen can be considered to have a low density. In fact, it is the least dense of all the elements.
Betelgeuse is a star, so there is little chance that anyone lives on it.
Jammu and Kashmir is a state in India; the population density is not so low for a region in the mountains - 56/km2.
They are correlated by volume weight/volume = density. For example, in a metal coin, the weight might not be much, but the volume is also very low, so it turns out that the density is high. Gases have almost no weight in a lot of volume, so their density is low.
Saturn has a very low density and it would be able to float on water. The density of Saturn is: 0.687 grams per cubic centimeter.
1. It has more gravitational force exerted on other objects 2. It holds more energy than smaller objects
All the gas giants; in our Solar System, Saturn has the lowest density (less than the density of water).
Low-density lipoprotein
Saturn.
Charcoal has a low density because it is porous and lightweight.