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QJEEM21Phff16: JEE Main 2021 Physics - Class 12 JEEM21Phff16 Solution: What will be the magnitude of electric field at point O as…

What will be the magnitude of electric field at point O as shown in the figure? Each side of the figure is l and perpendicular to each other?

JEE Main 2021 (Online) 27th July Evening Shift Physics - Electrostatics Question 120 English

Multiple Choice Options

  • A 14πε0ql2{1 \over {4\pi {\varepsilon _0}}}{q \over {{l^2}}}
  • B 14πε0q(2l2)(22−1){1 \over {4\pi {\varepsilon _0}}}{q \over {(2{l^2})}}\left( {2\sqrt 2 - 1} \right)
  • C q4πε0(2l)2{q \over {4\pi {\varepsilon _0}{{(2l)}^2}}}
  • D 14πε02q2l2(2){1 \over {4\pi {\varepsilon _0}}}{{2q} \over {2{l^2}}}\left( {\sqrt 2 } \right)

Step-by-Step Verified Solution

E1=kql2=E2{E_1} = {{kq} \over {{l^2}}} = {E_2}

E3=kq(2l)2=kq2l2{E_3} = {{kq} \over {{{(\sqrt 2 l)}^2}}} = {{kq} \over {2{l^2}}}

E=2kql2−kq2l2=kq2l2(22−1)E = {{\sqrt 2 kq} \over {{l^2}}} - {{kq} \over {2{l^2}}} = {{kq} \over {2{l^2}}}\left( {2\sqrt 2 - 1} \right)

JEE Main 2021 (Online) 27th July Evening Shift Physics - Electrostatics Question 120 English Explanation

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