Four positive point charges + q are kept at the four corners of a square of side l . The net electric field at the midpoint of any one side of the square is ( take 1 4 π ∈ 0 = k )

Question

Four positive point charges + q are kept at the four corners of a square of side l . The net electric field at the midpoint of any one side of the square is ( take 1 4 &#960; &#8712; 0 = k )

Quantrex Academy · Accepted Answer

Correct answer: B. 16 &#160; k q 5 5 l 2

The electric field of E C &#160; &#38; &#160; E D are equal and opposite so they cancel out each other, now net electric field at the midpoint of one side is, 2 E A cos &#952; because E A = E B , so, E n e t = 2 &#215; k &#215; q l 2 + l 2 2 cos &#952; E n e t = 2 &#215; k &#215; q l 2 + l 2 2 2 &#215; l l 2 + l 2 2 E n e t = 16 &#160; k q 5 5 l 2

Four positive point charges + q are kept at the four corners of a square of side l . The net electric field at the midpoint of any one side of the square is ( take 1 4 π ∈ 0 = k )

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Correct answer

Step-by-step solution

More from Electrostatics

Four positive point charges + q are kept at the four corners of a square of side l . The net electric field at the midpoint of any one side of the square is ( take 1 4 &#960; &#8712; 0 = k )

Options

Correct answer

Step-by-step solution

More from Electrostatics

Four positive point charges + q are kept at the four corners of a square of side l . The net electric field at the midpoint of any one side of the square is ( take 1 4 π ∈ 0 = k )