The figure shоws three оbjects (X, Y аnd Z) thаt hаve charges , , and , respectively. The оbjects are held on a fixed axis positioned shown. The magnitude of the electrostatic force exerted by object Y on object Z is . What is the magnitude of the net electrostatic force exerted on object Y due to the other two objects? On the left, X of charge negative 4q at position negative a, at center Y of charge positive q at position zero, and on the right Z of charge negative q at position a.