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Exercise 1905Calculus › Multivariable calculus › Vector calculusL1Added 3 Nov 2026

Flux through a cube

#divergence#cube#flux

Statement

Compute the outward flux of F⃗=(x2,0,0)\vec F=(x^2,0,0) through the cube [0,1]3[0,1]^3.

Hint

div⁡F⃗=2x\operatorname{div}\vec F=2x; integrate over the cube.

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Solution

Divergence. div⁡F⃗=2x\operatorname{div}\vec F=2x.

Integral. ∭[0,1]32x dV=2⋅12=12⋅1=1\iiint_{[0,1]^3}2x\,dV=2\cdot\frac12=\frac12\cdot1=1.

Conclusion. Flux =1=1.