Estimate the volume of a piece of molecular cloud that has the same amount of water as your body.

Question:

The water molecules now in your body were once part of a molecular cloud. Only about onemillionth of the mass of a molecular cloud is in the form of water molecules, and the mass density of such a cloud is roughly 2.0×10−21 g/cm^3.

Estimate the volume of a piece of molecular cloud that has the same amount of water as your body.

The volume of cloud that has the same density as the amount of water in our body is 1.4×10²⁵ cm³

Explanation:

Here, we have mass density of cloud  =  2.0×10⁻²¹ g/cm^3

Density = Mass/Volume

Volume = Mass/Density =   If the mass is 40 kg and the body is made up of 70% by mass of water, we have

28 kg water = 28000 g

Therefore the Volume = 28 kg/ 2.0×10⁻²¹ g/cm^3 = 1.4×10¹⁹ m³ = 1.4×10²⁵ cm³.

Therefore, the volume of cloud that has the same density as the amount of water in our body = 1.4×10²⁵ cm³.

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.

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hope this