a racing car that has a mass of 1500 kg is accelerating at 5.0 m/s square. The car experiences a lift force of 600 N up and 1000 N down. find the driving force needed to keep the car driving if (MU) for the car is 1.0.
the answer is 2.26 x 10 to the power of 4 N
The respected 9/eleven value document would not declare that the steel melted. Above approximately 4 hundred ranges the flair of steel starts off to be decreased; above a million,000 ranges it extremely is softened and weakened substantially. Why do you think of of blacksmiths heat temperature steel in a hearth previously they hammer it into shape? on a similar time as taken one after the quite a few, neither the hearth, nor the destruction of 60% of the form’s inner shape indoors the end result web pages, would have been sufficient to place across down the homes by using themselves. If the homes have been completely intact even a catastrophic hearth ought to now no longer have weakened them to an quantity that they’d have collapsed. Your theory some “extensive spike in rigidity” would not make any adventure to me. Any will develop in temperature ought to ultimate now return to common the on the spot the stress dissipated. additionally enable me ingredient out the the plane and any flying debris weren’t traveling at supersonic speeds, so as that they gained’t reason lots substantial “ask your self compression” of air. in spite of everything interior the adventure that your theory became properly desirable the homes would have collapsed desirable away, now no longer after fifty six minutes and 102 minutes later, respectively. The ingredient that impacts MAX flame temperature is oxygen concentration. the only thank you to furnish a flame heat sufficient to soften steel is to word organic and organic oxygen. Atmospheric air is purely 21% oxygen. there is not any gas which produces a flame heat sufficient to soften steel on a similar time because it extremely is burned in backyard. besides to the hearth indoors the WTC became frequently a “diffusion” form flame the area there is unfavourable mixing of gas and air, by way of fact of this the classic flame temperatures ought to be critically under the theoretical optimal if the gas/air have been thoroughly mixed. None the fewer, temperatures of a million,000, or perhaps a million,2 hundred ranges would have been reached. it extremely is surely below the melting ingredient of steel yet as i discussed it extra effective useful than sufficient to make uncomplicated structural steels extremely gentle and susceptible.