Assume that charge −q−q-q is placed on the top plate, and +q+q+q is placed on the bottom plate. What is the magnitude of the electric field EEE between the plates?

Magnitude of electric field = E = q/Aε0

Explanation:

Consider plates are placed at a distance of d. As given in the question the charge stored on the plates have magnitude q and given by:

                                          q = CV

And  

                                          V = q/C    ……. (i)

The capacitance is given by the following equation:  

                                         C = Aε0/d ……. (ii)

Put equation (ii) in (i) ,

                                          V = qd/ Aε0 …..(iii)    

The electric field is defined as:  

                                            E = V/d   …… (iv)

Put equation (iii) in (iv),

                                            E = qd/ Aε0d

                                            E = q/Aε0

Hence, the magnitude of electric field will be q/Aε0 .

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