An Application for Me
Poo, I'm gonna have to call you wrong on your answer. Although the radius does decrease at a constant rate, the relationship between the volume of a sphere and the radius is not linear. Therefore, your answer of 19 in^3/min is correect as the average rate of shrinkage for the first 28 minutes. However, in the next 28 minutes, the jawbreaker only shrinks at an average of 13.6 in^3/min. Therefore, the jawbreaker's decrease in size can only be expressed as an equation. Since I'm lazy, that's all I'm going to contribute for now... but since it was Poo's question anyway, I'll let someone else figure out the actual equation.
r i = 7dig1tal wrote:good luck poo bear
lang qualifier question:
Pythagoras the Platypus is eating a really, really big jawbreaker. The jawbreaker has a radius of 7 inches. As a member of the Lang Clan, Pythagoras knows that it is against the rules to bite the jawbreaker, so he must suck on it until it is gone. Assuming that the radius decreases at a constant rate, and after 28 minutes have passed it has a radius of 6 inches, at what rate is the volume of the jawbreaker decreasing then?
v = 4/3 * pi * (r - t/28 )^3
v' = 4 * pi * (r - t/28 )^2 * dv/dt
there ya go
"Be excellent to eachother" - Bill and Ted's Excellent Adventure
Bigg Cheese: Shut up!!!!!!! It's Californitucky now.
Bigg Cheese: Shut up!!!!!!! It's Californitucky now.
sorry, i didnt think too much into it, and as i always do, i read the question wrong. i wrote it down myself to figure out as the volume decreases constantly. my bad, that's why i thought it was too easy. sorry. yes, presto and i are roomies. been friends since like 9th grade. oh well. anywho, ill get back with an answer sometime, maybe
crim, soh-cah-toa (so-ka-toe-a), thats the main part of trig, unless you have an ass for a teacher like i did for geometry, i mean he even came in drunk a few times
digital, was that question from something or did you just make it up?
poo, yo 8)
wonder if the question can be simplified more... digital? you asked it.
digital, was that question from something or did you just make it up?
poo, yo 8)
wonder if the question can be simplified more... digital? you asked it.
"Be excellent to eachother" - Bill and Ted's Excellent Adventure
Bigg Cheese: Shut up!!!!!!! It's Californitucky now.
Bigg Cheese: Shut up!!!!!!! It's Californitucky now.
yeah, Mr. Pasquale in chelmsford high school is the man! First off, he starts each day with something completly unrelated to math, just current events or things he sees in the paper, or even just some fun facts, and he still teachs more than any other teacher i've ever had.
"Be excellent to eachother" - Bill and Ted's Excellent Adventure
Bigg Cheese: Shut up!!!!!!! It's Californitucky now.
Bigg Cheese: Shut up!!!!!!! It's Californitucky now.
i pulled off the net. i didn't expect it to be answered so well. i just wanted to see if it would be answered creatively.Kalign.Lang wrote: digital, was that question from something or did you just make it up?
wonder if the question can be simplified more... digital? you asked it.
Immense as whales, the motion of whose vast bodies can in a peaceful calm trouble the ocean til it boil.
Kalign.Lang wrote:dig1tal wrote:
v = 4/3 * pi * (r - t/28 )^3
v' = 4 * pi * (r - t/28 )^2 * dv/dt
there ya go
i don't know if that deriv is right?? don't you need to take the deriv of whats inside the brackets as well, and multiply the whole thing by it. the chain rule or something. and why are you multiplying by dv/dt. v' = dv/dt, so if you divide it back to the other side, it'd be 1 = 4*pi... i just dont think that'd work. and can't you substitute the 7 with r, because you know the max radius, and to find any other radius, its 7 - the time thing??
idk, but oh well
maybe i did it wrong, don't know, don't have time to check (another lab to do, shouldn't even be on the forum right now) but i did take the derivitive of the inside, v' is dv/dr in this case, not dv/dt, and thats why theres nothing about the r outside the brackets, its deriv is 1. I'm thinking maybe it should be (dv/dt)/28 though instead of dv/dt
or should it be something like dt/dr... can't remember, which goes where in the what now?
or should it be something like dt/dr... can't remember, which goes where in the what now?
"Be excellent to eachother" - Bill and Ted's Excellent Adventure
Bigg Cheese: Shut up!!!!!!! It's Californitucky now.
Bigg Cheese: Shut up!!!!!!! It's Californitucky now.