# Consider a uniform electric field E = 3 × 103 îN/C. (a) What is the flux of this field through a square of 10 cm on a side whose plane is parallel to the yz plane? (b) What is the flux through the same square if the normal to its plane makes a 60° angle with the x-axis?

420 Points
13 years ago

Dear Sri

Flux φ=E.A

in first case E is along x axis and area vector is also along x axis since the area is parallel to yz plane

φ=EA*cos00=EA=3x103 x(0.1)2 = 30 Nm2/C

in second case

E is along x axis and area vector that is normal is making 60 with x axis

Φ=EA*cos600=EA/2=15 Nm2/C

All the best.

AKASH GOYAL

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Rishi Sharma
3 years ago
Dear Student,

Area A=(0.1)2=0.01m2
Flux ϕ=EAcosθ
(i)θ=0o
ϕ=3×103×0.01×cos0o
⟹ϕ=30Nm2/C
(i)θ=60o
ϕ=3×103×0.01×21​
⟹ϕ=15Nm2/C

Thanks and Regards