Question #b0cef

1 Answer
Jun 15, 2015

The mass of air inside the balloon is 630 kg.
The total weight of the balloon is 8900 N.

Explanation:

So, you know that you have a balloon filled with air. The volume of the balloon is equal to #"700 m"^3#.

The density of the air will tell you what mass of air occupies exactly #"1 m"^3#. Since you know the volume of the balloon, you can use the density of the air to help you determine what the mass of the air is.

#700cancel("m"^3) * "0.90 kg"/(1cancel("m"^3)) = color(green)("630 kg")#

To get the total weight of the balloon, you need to calculate its total mass first. Since the material and equipment add a mass of 280 kg to the mass of air, the total mass will be

#m_"total" = m_"air" + m_"not air"#

#m_"total" = 630 + 280 = "910 kg"#

This means that the total weight of the balloon will be

#G_"total" = m * g = "910 kg" * 9.8"m"/"s"^2 = "8918 N"#

I'll leave both values rounded to two sig figs, despite the fact that you only gave one sig fig for the volume of the balloon.

#G_"total" = color(green)("8900 N")#