Carrying power of the aircraft which is lighter than air, is defined by its volume and also density of the gas filling it. The last, in turn, depend on its structure and temperature. Some balloons fill with hot air, and others - light gases. Also it is necessary to consider the mass of the cylinder.
Instruction
1. The thermal balloons differently called montgolfiers contain in themselves air of the same structure, as outside. It differs from external in only temperature: the it is higher, the density is less. For atmospheric air under normal conditions (20 degrees Celsius, 760 millimeters of mercury) it makes 1.2041 kgm³, and at 100 degrees Celsius (typical air temperature in a montgolfier) and the same pressure - 0.946 kgm³. Knowing the cover volume (which is previously transferred to cubic meters), calculate the mass of gas in it in both cases: m1=ρ1V where m1 is the mass of air under normal conditions, kg, ρ1 - density under normal conditions, kgm³, V - the volume of a sphere, m³; m2=ρ2V where m2 is the mass of air in a heated state, kg, ρ1 - density in a heated state, kgm³, V - the volume of a sphere, m³;
2. Calculate carrying power without the mass of a cover. Express it in kilograms of force (kgf) in the beginning: F1=m1-m2 where F1 is carrying power without the mass of a cover, kgf, m1 is the mass of air under normal conditions, the kg, m2 is the mass of air in a heated state, kg.
3. Subtract the mass of a cover from carrying power: F2=F1-mob where F2 is carrying power taking into account the mass of a cover, kgf, F1 is carrying power without the mass of a cover, kgf, mob is the mass of a cover, kg.
4. If necessary transfer carrying power taking into account the mass of a cover from stand-alone units (kgf) to SI units - newtons, F2 [kgf] - it expressed in kilograms of force, g - the acceleration of gravity equal of 9.822 m/s².
5. In case the sphere is filled not with hot air, but light gas, carry out calculations also, having substituted instead of ρ2 density of this gas in normal conditions (some increase in pressure in a cylinder due to gas squeezing by its walls can be neglected). Density of hydrogen is equal 0, 0899 kgm³, helium - 0.17846 kgm³. In spite of the fact that hydrogen at the same volume is capable to create considerably big carrying power, its application in balloons is limited because of fire danger. Helium is applied much more often, despite an essential shortcoming - ability to disappear through cover walls.