Question R9 Q2 - NSB Middle School 2009

A blimp or airship that uses helium as its lifting gas primarily controls its buoyancy by doing which of the following:

W) adding or removing small amounts of hydrogen gas because it is lighter than helium

X) heating or cooling the helium gas within the outside bladder of the blimp

Y) intaking or venting air

Z) producing or destroying helium gas

Science Bowl Question