SOLUTION: A vector has magnitude 6.0 units due east, vector B points due north. Find a) the magnitude of B if A+B points 60° north of east? b) the magnitude of A+B

Algebra ->  Vectors -> SOLUTION: A vector has magnitude 6.0 units due east, vector B points due north. Find a) the magnitude of B if A+B points 60° north of east? b) the magnitude of A+B      Log On


   



Question 1206230: A vector has magnitude 6.0 units due east, vector B points due north. Find
a) the magnitude of B if A+B points 60° north of east?
b) the magnitude of A+B

Answer by ikleyn(52817) About Me  (Show Source):
You can put this solution on YOUR website!
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A vector has magnitude 6.0 units due east, vector B points due north. Find
a) the magnitude of B if A+B points 60° north of east?
b) the magnitude of A+B
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        In this post, first sentence is incorrect.  Instead of " A vector has magnitude  6.0  units due east, . . . "
       should be  " Vector  A  has magnitude  6.0  units due east, . . . ".

       It may seems like a small microscopic thing,  but in Math every word matters,  and the order
        of the words does matters,  too.  Wrong order of words makes the post non-sensical.

        So,  I will solve the problem,  edited this way.


(a)  Since in the coordinate plane vector A is vertical and vector B is horizontal, 

     vector A+B has x-component Ax = 6 = |A|, the magnitude of vector A, 
            and has y-component |B|, the magnitude of vector B.


     Since tan(60°) = sqrt%283%29,  it implies that  abs%28B%29%2F6 = sqrt%283%29.

     From this equation, we get |B| = 6%2Asqrt%283%29 = 10.3923  (rounded).


     It gives the ANSWER to question (a) :  the magnitude of vector B is  6%2Asqrt%283%29 = 10.3923  (rounded).



(b)  Now we know that x-component of vector A+B is the same as x-component of vector A, i.e. 6,
     and we know that y-component of vector A+B is the same as y-component of vector B, i.e. 6%2Asqrt%283%29.

     Hence, the magnitude of A+B is  sqrt%286%5E2+%2B+%286%2Asqrt%283%29%29%5E2%29 = sqrt%286%5E2%2B3%2A6%5E2%29 = sqrt%284%2A6%5E2%29 = 2*6 = 12.


     It gives the ANSWER to question (b) :  the magnitude of A+B is 12.

Solved.