the correct option is a) shall increase along the positive x-axis.
In the figure, two positive charges q2 and q3 fixed along the y-axis, exert a net electric force in the +x direction on a charge q1 fixed along the x-axis. If a positive charge Q is added at (x,0) the force on q1 a) shall increase along the positive x-axis b) shall decrease along the positive x-axis c) shall point along the negative x-axis d) shall increase but the direction changes because of the intersection of Q with q2 and q3
In the figure, two positive charges q2 and q3 fixed along the y-axis, exert a net electric force in the +x direction on a charge q1 fixed along the x-axis. If a positive charge Q is added at (x,0) the force on q1 a) shall increase along the positive x-axis b) shall decrease along the positive x-axis c) shall point along the negative x-axis d) shall increase but the direction changes because of the intersection of Q with q2 and q3