1. A hot-air balloon achieves its buoyant lift with heating the air inside the balloon, which makes it less dense than the air outside. Suppose the volume of a balloon is 1600 m3 and the needed lift is 2200 N (rough estimate of the weight of the equipment and passenger). Compute the temperature of the air inside the balloon which will produce the required lift. Suppose that the outside air temperature is 0°C and that air is an ideal gas under these conditions.
What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.)
2. An ordinary glass is full to the brim with 359.0 mL of water at 100°C. If the temperature decreased to 22°C, how much water could be added to the glass?