Question
A vector ( overrightarrow{mathrm{Q}} ) which has a magnitude of 8 is added to a vector ( overrightarrow{mathrm{P}} ) which lies along ( mathrm{x} ) -axis. The resultant of two vectors lies along ( y ) -axis and has magnitude twice that of ( vec{P} ). The magnitude of ( vec{P} ) is

A vector ( overrightarrow{mathrm{Q}} ) which has a magnitude of 8 is added to a vector ( overrightarrow{mathrm{P}} ) which lies along ( mathrm{x} ) -axis. The resultant of two vectors lies along ( y ) -axis and has magnitude twice that of ( vec{P} ). The magnitude of ( vec{P} ) is
(a) ( frac{16}{sqrt{5}} )
(b) ( frac{12}{sqrt{5}} )
(c) ( frac{8}{sqrt{5}} )
(d) ( frac{6}{sqrt{5}} )
Solution

Option (c) ( frac{8}{sqrt{5}} ) is the right answer. Check detailed solution given above.