In Figure 21.15 the magnitude of the electric field is 1000V/m, and the field is at an angle of 30oto the outward-going normal. What is the flux on the small rectangle whose dimensions are 1mmby2mm ?

Short Answer

Expert verified

1.732×10-3Vm

Step by step solution

01

Identification of given data

Magnitude of the electric field is E=1000V/m

Area of rectangle is ΔA=1mm×2mmor2×10-6m2

The field is at an angle ofθ=30o

02

Significance of electric flux

The number of electric lines of force (or electric field lines), a characteristic of an electric field, that cross a specific area is known as electric flux.

ϕ=E×ΔA×cosθ

03

Determining the flux on the small rectangle whose dimensions are1 mm by 2 mm

Using equation (i)

ϕ=E×ΔA×cosθ=1000V/m×2×10-6m2×cos30o=1.732×10-3Vm

Hence the flux on the small rectangle is1.732×10-3Vm

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