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calculus help...plz explain and answer question...i totally dont know what they are...studying on my own
 11 months ago
 11 months ago
calculus help...plz explain and answer question...i totally dont know what they are...studying on my own
 11 months ago
 11 months ago

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phiBest ResponseYou've already chosen the best response.1
r is a position vector... the position of a point that changes with time. it has components in the x direction (the "ith" component) and y direction the velocity of the point is dr/dt (derivative with respect to time) you take the derivative of each component separately.... you get a new vector that represents the velocity in the x and y dimensions...
 11 months ago

phiBest ResponseYou've already chosen the best response.1
it is not obvious, but they mean v is the velocity vector and a is the acceleration vector (2nd derivative of r, and the 1st derivative of v)
 11 months ago

Best_MathematicianBest ResponseYou've already chosen the best response.0
(tsint)i = (1cost)i = (sint)i (1cost)j = (sint)j = (cost)j f(x) f'(x) f''(x)
 11 months ago

phiBest ResponseYou've already chosen the best response.1
r= (tsin t) i + (1cos t) j v= dr/dt = (1cos t) i + sin t j or v= < (1cos t, sin t> the magnitude of v is found by doing the dot product v^2 = v dot v and v = sqrt( v dot v)
 11 months ago

Best_MathematicianBest ResponseYou've already chosen the best response.0
what is dot product
 11 months ago

phiBest ResponseYou've already chosen the best response.1
Khan has videos on vectors. See http://www.khanacademy.org/math/linearalgebra/vectors_and_spaces/dot_cross_products/v/vectordotproductandvectorlength Here is one from the physics playlist http://www.khanacademy.org/science/physics/electricityandmagnetism/v/thedotproduct which might be better. But the dot product is the sum of the product of corresponding elements. In this case < (1cos t, sin t> dot < (1cos t, sin t> = (1cos t)^2 + (sin t)^2 which simplifies to v = 2(1 cos t)
 11 months ago

Best_MathematicianBest ResponseYou've already chosen the best response.0
ohk got it...so how to get minimum nd maximum values
 11 months ago

phiBest ResponseYou've already chosen the best response.1
we know cos t has a max of +1 and a min of 1, so v ranges between 2(11) and 2(1  (2)) or 0 and 4
 11 months ago

phiBest ResponseYou've already chosen the best response.1
** 2(1  (1)) or 0 and 4
 11 months ago

Best_MathematicianBest ResponseYou've already chosen the best response.0
plz carry on
 11 months ago

phiBest ResponseYou've already chosen the best response.1
a= < sin t , cos t> can you find its dot product (that gives you a^2 )
 11 months ago

Best_MathematicianBest ResponseYou've already chosen the best response.0
yes it is 1
 11 months ago

Best_MathematicianBest ResponseYou've already chosen the best response.0
sin^2t+cos^2t = 1
 11 months ago

Best_MathematicianBest ResponseYou've already chosen the best response.0
am i on track?
 11 months ago

Best_MathematicianBest ResponseYou've already chosen the best response.0
ok so min and max for velocity is 0 and 4 repectively and min and max for acceleration is 1 and 1...correct?
 11 months ago

phiBest ResponseYou've already chosen the best response.1
the magnitude of the acceleration is always 1, but its direction is changing.
 11 months ago

Best_MathematicianBest ResponseYou've already chosen the best response.0
oh ya but we do not need to care about direction...right?
 11 months ago

phiBest ResponseYou've already chosen the best response.1
you might care if you were trying to analyze what is going on... but you don't need the direction if all you care about is the magnitude.
 11 months ago

Best_MathematicianBest ResponseYou've already chosen the best response.0
ok so how to do rest of the part
 11 months ago

phiBest ResponseYou've already chosen the best response.1
I am not sure what they want for a plot... for the smaller hoop, make the frequency twice as fast. that means in sin t and cos t replace t with 2t this will make the hoop spin twice as fast.
 11 months ago

Best_MathematicianBest ResponseYou've already chosen the best response.0
ok so what is the vector function that models the behavior
 11 months ago
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