Question

Fig. shows three point charges +2q, – q and +3q. The charges +2q and –q are enclosed within a surface ‘S’. What is the electric flux due to this configuration through the surface ‘S’? [CBSE Delhi 2010]

January 13, 2024

Answer

Electric Flux = $1\over \varepsilon_0$ × (Net charge enclosed within the surface)

= $1\over \varepsilon_0$ (2q – q) = $1\over \varepsilon_0$ q

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