Question

Three forces are acting on a particle as shown in the figure. To have the resultant force only along the Y-direction, the magnitude of the maximum additional force needed is

A. `0.866 N`
B. `1.732 N`
C. `0.5 N`
D. `4 N`

Answer 1

Correct Answer - C
Resulant is along Y-axis. So, the component of resultant force along X-axis should be zero.
`:. SigmaF_(x)=0`
or `1 sin 30^(@)+ 2sin30^(@)- 4cos60^(@)+F_(0)=0`
`:. F_(0)= -1/2-1+2= 1/2= 0.5N`