A particle is placed at the origin of the coordinate system. Two forces of magnitude `20N & 10N` act on it as shown in figure. It is found that it starts moving towards the point `(1,1)` . The net unknown force acting on the particle at this position can be `:`

Options

A. `15sqrt(2)` at angles `45^(@)` with positive `x` axis
B. `5sqrt(2)` at angle `135^(@)` with positive `x` axis
C. `5sqrt(2)` at angle `-45^(@)` with positive `x` axis
D. None of these

Answer

C

Explanation

Check the options so that the resultant force comes towards `(1,1). i.e., F_(xn et)=F_(y n e t)`
`(` There exist inifnite solutions because the acceleratio is not given, for example