Apuddle of water on the porch disappears after a few days. which statement justifies this phenomenon?
water loses energy to the atmosphere and is converted to steam.
water loses energy and freezes to ice, which is transparent.
water gains energy from sunlight and is converted to vapor.
water gains energy from sunlight and freezes to ice.
water loses energy causing the water molecules to shrink and disappear.
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Hot air balloons float in the air because of the difference in density between cold and hot air. in this problem, you will estimate the minimum temperature the gas inside the balloon needs to be, for it to take off. to do this, use the following variables and make these assumptions: the combined weight of the pilot basket together with that of the balloon fabric and other equipment is w. the volume of the hot air inside the balloon when it is inflated is v. the absolute temperature of the hot air at the bottom of the balloon is th (where th> tc). the absolute temperature of the cold air outside the balloon is tc and its density is ďc. the balloon is open at the bottom, so that the pressure inside and outside the balloon is the same. as always, treat air as an ideal gas. use g for the magnitude of the acceleration due to gravity.

What would happen to a volleyball left outside in the winter? o o o o a. it would expand. b. it would lose air. c. it would shrink. d. it would explode.

What is the scientific name for weight?