More info needed. How much does 0.4 cubic feet of what weigh? Air? Lead? Water? Dirt?
With a barometer.
They are very reactive to air and water, they are very soft. and they don't weigh very much
Greenhouse gasses are NOT "obviously lighter than air"; carbon dioxide is significantly heavier than air.One way to weigh something that's lighter than air is to weigh it in a vacuum.
You can blow up a balloon and then weigh the balloon and minus it from the original weight of the balloonAnswer:Weighing air is problem because of the buoyant forces at work. If you have flattened paper bag and weigh it then open it up (effectively filling it with air), and weigh it again you find the weight is the same. In the case of a balloon, a filled balloon will weigh more than an empty balloon as it is filled with compressed air due to the tension of the balloon skin. You have no idea of the volume of room pressure air is in it.To determine this you could inflate the balloon with known volume of air using bicycle pump. Simple math would identify the volume transferred with each stroke. By knowing the weight before filling, the weight after filling, and the volume transferred it would be possible to calclate the weight per meter (or cubic foot) of room pressure air.
a puck
air hockey
no, unless an infraction (foul) has occured, the air hockey puck must remain hands free at all times. - Chow
Spit on it.
Simply catching the puck while it is in mid-air, not to be confused with freezing the puck which is causing a whistle by covering the puck with your hand.
you need 2 sticks and then you have to hit it in the other players goal. (it is a 2 player game)
Gravity keeps the puck near the table.
yes you get the goal
False
yes, it just has less friction across the table from the air pushing up on the puck through the holes.
If a puck is placed on the ice so that it isn't moving it will stay where it is placed. That's inertia.If a player whacks the puck straight for the net and no other player gets in the way then the puck will go into the net. The only thing that could slow the puck would be the tiny friction between the ice and the puck but that doesn't amount to much. The air turbulence around a puck must have a slight effect too. But the overall straight line trajectory of the puck is inertia too.In ordinary life, things 'at rest stay at rest' and things that are moving move in straight lines unless additional forces act on those things.
I think because it is harder to slapshot a puck into the air than it is a ball used in roller hockey.