If the resultant of two equal forces inclined at `60^(@)` to each other is `sqrt(3)Q`, will be their resultant if they are inclied at `120^(@)` to each other?

Options

A. `(sqrt(3)Q)/2`
B. `sqrt(3)Q`
C. `Q/2`
D. Q

Answer

D

Explanation

`|vec(F)_(1)|=|vec(F)_(2)|=F`
`F_(res)=2F cos alpha`
`=2F cos 30^(@) =sqrt(3) theta` (given)
`rArr F xx sqrt(3) =sqrt(3) thetarArr F =theta....(i)`

`|vec(F)_(1)|=|vec(F)_(2)|=F`
`F_(res)=2F cos a|_(2)" " alpha= 120^(@)`
=`2F cos 60^(@)`