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Zara26
Group Title
find the components of the vector 3i+2j+8k in the direction of the vector 2i+2j+2k
 2 years ago
 2 years ago
Zara26 Group Title
find the components of the vector 3i+2j+8k in the direction of the vector 2i+2j+2k
 2 years ago
 2 years ago

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sam30317 Group TitleBest ResponseYou've already chosen the best response.0
3i+2j+8k +2i+2j+2k ______________ 5i +4j +10k Check if its right. Been a looong time since ive done this.
 2 years ago

dumbcow Group TitleBest ResponseYou've already chosen the best response.2
im guessing find magnitude of 1st vector > sqrt(3^2 + 2^2+8^2) = sqrt(77) and then find components of directional vector with same magnitude unit vector of 2nd vector = 1/sqrt3 , 1/sqrt3 , 1/sqrt3 multiply by magnitude > sqrt(77/3) i + sqrt(77/3) j + sqrt(77/3) k
 2 years ago

Zara26 Group TitleBest ResponseYou've already chosen the best response.0
r u sure about the answer
 2 years ago

sam30317 Group TitleBest ResponseYou've already chosen the best response.0
.....NO!!! Im not confident thats right. I suggest asking this question in the physics study group. And look at t his site: http://www.ehow.com/how_8396057_determineresultantvector.html
 2 years ago

dumbcow Group TitleBest ResponseYou've already chosen the best response.2
im pretty sure i did it right as long as i understood the question correctly. you taking 1st vector and placing it so its going same direction as 2nd vector but has same magnitude...correct?
 2 years ago

Zara26 Group TitleBest ResponseYou've already chosen the best response.0
am not sure...am still trying to solve it
 2 years ago

sam30317 Group TitleBest ResponseYou've already chosen the best response.0
R u doing college physics?? Did u read anything about "dot product"??
 2 years ago

wasiqss Group TitleBest ResponseYou've already chosen the best response.0
dumb cow is correct ,
 2 years ago

wasiqss Group TitleBest ResponseYou've already chosen the best response.0
wait, ik the right answer.
 2 years ago

wasiqss Group TitleBest ResponseYou've already chosen the best response.0
we take the dot product of first vector with unit vector of second
 2 years ago

sam30317 Group TitleBest ResponseYou've already chosen the best response.0
Instead of adding, do what I showed you in the SAME set up, except u multiply straight down: (3*2)+(2*2)+(8*2) = 26
 2 years ago

sam30317 Group TitleBest ResponseYou've already chosen the best response.0
Yeaaah!! I dont remember how to get angle..if its needed
 2 years ago

wasiqss Group TitleBest ResponseYou've already chosen the best response.0
zara my answer is the right one, cause i did this question last day
 2 years ago

FoolForMath Group TitleBest ResponseYou've already chosen the best response.1
\(<3,2,8> . <2,2,2> = 6 + 4+16 = 26\) \[<2,2,2>= \sqrt{12} \] Vector component of \(\vec{a} \)in the direction of \(\vec{b}\) is given by \( \frac {\mathbf{a} \cdot \mathbf{b}} {\mathbf{b} } \frac {\mathbf{b}} {\mathbf{b}} \) Hence, \(\frac {26}{12} <2,2,2> = \frac {13}6<2,2,2> \)
 2 years ago

FoolForMath Group TitleBest ResponseYou've already chosen the best response.1
I have assumed that you meant vector component and not the scalar one.
 2 years ago

FoolForMath Group TitleBest ResponseYou've already chosen the best response.1
@dumbcow: I am not sure from where you came up with that definition, can you please explain? http://en.wikipedia.org/wiki/Vector_projection
 2 years ago

anonymoustwo44 Group TitleBest ResponseYou've already chosen the best response.0
foolformath's right
 2 years ago

dumbcow Group TitleBest ResponseYou've already chosen the best response.2
@foolFormath, oops did not recognize this as vector projection...for some reason i thought the magnitude of 1st vector should remain the same
 2 years ago
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