1. The current (critical) density of our universe is pe = 10-26kg/m³. Assume the universe isfilled with cubes with equal size that each contain one person of m = 100kg. What wouldthe length of the side of such a cube have to be in order to give the correct critical density?How many hydrogen atoms would you need in a box of 1 m³ to reach the critical density?The matter we know, which consists mostly of hydrogen, constitutes only 4.8% of the currentcritical energy density of our universe. So how many hydrogen atoms are actually in a boxof 1 m3 in our universe? Deep space is very empty and a much better vacuum than we canobtain on earth in a laboratory.

Given: Critical density of universe = 10-26 kg/m3 Mass of 1 person = 100 kg

The current (critical) density of our universe is Pc ~ 10-26kg/m³. Assume the universe is filled with cubes with equal size that each contain one person of m = 100kg. What would the length of the side of such a cube have to be in order to give the correct critical density? How many hydrogen atoms would you need in a box of 1 m3 to reach the critical density? The matter we know, which consists mostly of hydrogen, constitutes only 4.8% of the current critical energy density of our universe. So how many hydrogen atoms are actually in a box of 1 m3 in our universe? Deep space is very empty and a much better vacuum than we can obtain on earth in a laboratory.

The current (critical) density of our universe is Pc ~ 10-26kg/m³. Assume the universe is filled with cubes with equal size that each contain one person of m = 100kg. What would the length of the side of such a cube have to be in order to give the correct critical density? How many hydrogen atoms would you need in a box of 1 m3 to reach the critical density? The matter we know, which consists mostly of hydrogen, constitutes only 4.8% of the current critical energy density of our universe. So how many hydrogen atoms are actually in a box of 1 m3 in our universe? Deep space is very empty and a much better vacuum than we can obtain on earth in a laboratory.