Le foyer d'une chaudière, alimenté par du charbon, a un rendement de 75%. Ce foyer chauffe une chaudière contenant 1 m d'eau de 15 à 90°C à pression
normale.
a-Quelle est la masse du charbon utilisée ? Pouvoir calorifique du charbon est
8000 cal/g : c'est-à-dire que la combustion de 1 g de charbon fournit 8000 cal.
b- Calculer la puissance du foyer.
Solution :​

as the gila monster consumes the eggs or young of the desert cottontail and gambel's quail, thus its main food supply is only accessible for a restricted time duration every year. however, for this, the gila monsters exhibit three adaptations, which elevate their survival rate in the desert condition.  

first, is that they possess huge bodies, and can consume greater concentrations of food during a small period. secondly, they require to feed infrequently as they can accumulate fat in their tails. ultimately, their rate of metabolism is very low, so that they can burn their reservoirs of fat gradually.  

supercell thunderstorms are perhaps the most violent of all thunderstorm types, and are capable of producing damaging winds, large hail, and weak-to-violent tornadoes