Question

The flux of the electric field $\vec{E} = 24 \hat{i} + 30 \hat{j} + 28 \hat{k} \, N \, C^{-1} $ through an area of 20 $m^2 $ on the $yz$ plane is

• A. $480 \, N \, m^2 C^{-1}$
• B. $600 \, N \, m^2 C^{-1}$
• C. $560 \, N \, m^2 C^{-1}$
• D. $1640 \, N \, m^2 C^{-1}$

Answer 1

Answer: (A)

Here, $\overrightarrow{ E }=24 \hat{ i }+30 \hat{ j }+28 \hat{ k } N C ^{-1}$
$\overrightarrow{ S }=20 \hat{ i } m ^2$
Electric flux,$\phi=\vec{E} \cdot \vec{S}$
$=\left(24 \hat{ i }+30 \hat{ j }+28 \hat{ k } N C ^{-1}\right) \cdot\left(20 \hat{ i } m ^2\right) $
$=480 N m ^2 C ^{-1}$