- #1

bray d

- 10

- 0

**[SOLVED] mass of gas required to lift another mass**

## Homework Statement

A balloon contains gas of density G and is to lift a mass M, including the balloon but not the gas. Show that the minimum mass of gas required is m=(MG)/(A-G) where A is the atmospheric density.

## Homework Equations

Basic density mass relationships?

## The Attempt at a Solution

Obviously the density of the gas is less than the density of the atmosphere, thus the lifting force is possible. I'm just having a hard time seeing the relationships without actual numbers. I tried applying numbers to the situation but that hasn't seemed to help, like making G=.5 and A=1. I need a witty suggestion to jump start me. Thanks