is that brittle is inflexible, liable to break or snap easily under stress or pressure while flexible is capable of being flexed or bent without breaking; able to be turned, bowed, or twisted, without breaking; pliable; not stiff or brittle.s that brittle is (uncountable) a confection of caramelized sugar and nuts while flexible is (chiefly|engineering|and|manufacturing) something that is flexible. As adjectives the difference between brittle and flexible. As nouns the difference between brittle and flexible.
If you decrease the temperature of a fixed amount of gas at constant pressure, the combined gas law reduces to Charles's law. In this case, volume will also decrease. If you were to maintain a constant volume while decreasing the temperature, the pressure would also have to decrease in order to satisfy Gay-Lussac's law.
In fact, you can have a very nice weather in a high pressure zone, with clear sunny sky and little wind, but during daytime, the pressure drops a little to climb up again during the night. That is a normal diurnal variation of pressure; when it is hot, air rises and pressure drops a bit. It is not the drop in itself but the rate of fall that is the most important point and that's why some people have barographs that register the pressure over time. An old seafarer's rule is that a pressure fall of ten millibars (today, called hecto-Pascal) in eight hours is a certain sign of a gale force wind coming in. And that is the only thing that is 100 percent certain in meteorology; a pressure fall must be followed by a wind of air trying to fill again the lower pressure.