Two particles are fixed on an x axis. Particle 1 of charge 40 μC is located at x = -2.0 cm; particle 2 of charge Q is located at x = 3.0 cm. Particle 3 of charge magnitude 20 μC is released from rest on the y axis at y = 2.0 cm.

What is the value of Q if the initial acceleration of particle 3 is in the positive direction of

a) the x axis and

b) the y axis?