Q3 of 177 Page 24

Mark the correct alternative in each of the following:

Forces act along OA and OB. If their resultant passes through C on AB, then



Draw ON perpendicular to the line AB.


Let be the unit vector along ON,


The resultant force --------- (i)


The angles between and the forces , , are CON, AON & BON respectively,







R = 8


---------- (i)


Multiplying the equation (i) by 3,


----------(ii)


Also, ----------(iv)


Multiplying the equation (iv) by 5,


----------(v)


Adding equation (iv) & (v) respectively,






3AC = 5CB


Option(C)is the answer.

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