Question

ABC is an equilateral triangle charges + Q are placed at each corner the electric field intensity at the centroid of the triangle will be

Answer 1

Electric field at O is Zero.

Proof of this-
I hope this will help you

Answer 2

Answer:

The ‘electric field’ intensity at the ‘centroid of the triangle’ will be 0.

Explanation:

Electric field due to +Q charges of edge A, B and C at center is,

$E=\left(\frac{1}{4 \pi}\right) \times\left(\frac{Q}{r^{2}}\right)$

As shown in figure, $\bold{\mathrm{E}_{\mathrm{A}}=\mathrm{E}_{\mathrm{B}}=\mathrm{E}_{\mathrm{C}}}$  

Resultant of $\mathrm{E}_{\mathrm{B}} \text { and } \mathrm{E}_{\mathrm{C}}$,  

$\mathrm{E}_{\mathrm{R}}=\sqrt{E_{B}^{2}+E_{C}^{2}+2 E_{B} E_{C} \cos 120^{\circ}}$

But as $\mathrm{E}_{\mathrm{B}}=\mathrm{E}_{\mathrm{C}}$

$\mathrm{E}_{\mathrm{R}}=\sqrt{E_{B}^{2}+E_{B}^{2}+2 E_{B}^{2}\left(-\frac{1}{2}\right)}=\sqrt{E_{B}^{2}}=\mathrm{E}_{\mathrm{B}}$

Here as $E_{B} \text { and } E_{A}$ are equal in magnitude and in opposite direction, so electric field at o is zero.