Don't want answers obviously since I'm guessing you don't have a photographic memory and we're not really supposed to talk about the questions, but how were we supposed to separate the differentials for something that didn't have the second term? NO ONE in my school figured it out.
It was something like dW/dt=(1/25)(W-800)
It was something like dW/dt=(1/25)(W-800)
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dw/dt = (1/25) * (w - 800)
dw/(w-800) = dt / 25, separate the variables and then integrate.
ln(w-800) = t / 25 + C, exponentiate to get to the next step.
w - 800 = e ^ (t / 25 + c) = e ^ (t / 25) * e^c
w = e^c * e ^ (t / 25) + 800
dw/(w-800) = dt / 25, separate the variables and then integrate.
ln(w-800) = t / 25 + C, exponentiate to get to the next step.
w - 800 = e ^ (t / 25 + c) = e ^ (t / 25) * e^c
w = e^c * e ^ (t / 25) + 800
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i pretty much feel the same as you... I thought the free response was tricky, especially the one with the temperatures. There were even a few multiple choice ones that I wasn't too sure about.
Dammit I wish I realized what to do for that one! UGH! oh well there goes more points out the window...
Dammit I wish I realized what to do for that one! UGH! oh well there goes more points out the window...
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I remember tht one haha, i think it was dW/dt=(1/25)(W-300)... not 800 haha, at least for my test it was 300...
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i agree that question was absolutely impossible. nobody at my school was able to get it either! what did you think of the rest of the exam?