NEET Physics Mathematical Tools Questions Solved


Find electric field due to a uniformly charged, long and thin rod

[This question is only for Dropper and XII batch]

1. kλr

2. kλ2r

3. 2kλr

4. kλ4r

Concept Videos :-

#16 | Calculus: Differential Equation
#19 | Numericals

Concept Questions :-

To find electric field, we enclose the distribution in a Gaussian cylinder of radius r and length l.

The flux linked with the cylinder

E.dA= CurvedE.dA + FlatE.dA =E.(2πrl)cos0°+2EdA cos90°φtotal=E×2πrlBy Gauss law φ=qencε0=λ×lε0                  [where λ is linear charge density]E×2πrl=λ×lε0E=λ2πε0r

Variation of E with r is also shown graphically here            

Difficulty Level:

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