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Consider three vectors vector A, vector B, vector C. It is given that vector A and vector B lie in the x-y plane and the direction of vector C is along (+k^). Also, it is known that |vector A|=10 and |vector B|=6 units and the three vectors are related by the relation vector A=vector B - alpha(vector B X vector C), where alpha is some postive constant.
Now, if only the magnitude of vector C is doubled, then what should the magnitude of vector B be, for which vector A remains unchanged (both in magnitude and direction)?
Asked by sd8022567 | 09 Jun, 2022, 13:02: PM
Expert Answer
It is given that 
and 
are in x-y plane and 
is along z-axis .
and are in x-y plane and is along z-axis . , and are related as = - α ( × ) ...................... (1)let 
= α ( × ) .........................(2)
= α ( × ) .........................(2)Hence we get , + = .......................(3)
+ = .......................(3) From the given orientaion of vectors , we can see that is in x-y plane .
is in x-y plane . Hence , and are coplanar . is resultant of
, and are coplanar . is resultant of