Akilogram of aluminum metal and a kilogram of water are each warmed to 75 ∘c and placed in two identical insulated containers. one hour later, the two containers are opened and the temperature of each substance is measured. the aluminum has cooled to 35 ∘c while the water has cooled only to 66 ∘c.

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.

Used the balanced equation 2h2+ o2 - -> 2h2o. if you have 7.2 grams of o2 , how many grams of h2o can you produce ?

Aroller coaster is traveling at 13 mi./s when you purchase a hill that is 400 m long and down the hill exonerate at 4.0 m/s squared what is the final velocity of the posterior found your answer to the nearest number