Thread: The movie "The Transporter 3"

Hi,

I watched the movie "The Transporter 3" and something striked me. At one point our protagonist dives into a river with his car to get away from the goons. In an attempt to raise his car from the river bed, he leads the compressed air from the tires into some plactic he retrieves from the trunk of the car which he places above the car and attaches to the car it self. This way leading the rising air into the plactic forming kind of a balloon. This is done with all 4 wheels and he succesfully manages to rise the car to the surface and row to shore.

In case you havent seen the movie, I hope you understand what I tried to explain.

My question is:

Does compressed air have less buoyancy/lifting ability than uncompressed air? If not, then the mentioned procedure in the movie is not possible since the air was already in the tires of the car and thus making it rising without releasing it into balloons.

Regards, and thank you for your expert experience of the matter

@

i could easily be corrected here but I would say yes - compressed air has less buoyancy then uncompressed air.

I think this is basically as compressed air is denser - if it is allowed to expand (and held in a sealed environment) that environment will eventually be more buoyant as it would reach a point of being less dense then the water.

What compressed air does have is more potential energy and this might be where the confusion is...........?

Think of it like this: the scuba diver who is working on the sea floor needs to raise an object and uses the air from his regulator to fill a balloon attached to a bag, which rises to the surface for someone on the boat to gaf.

The scuba diver needs only a few pounds of weights to offset his bodies buoyancy, but I believe a scuba tank will sink on its own accord. I seem to recall my dad leaving filled tanks on the bottom near a dive site when he was doing underwater work.