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JEE Advanced2008PhysicsElectrostaticsActual

Paragraph: The nuclear charge ( Ze ) is non-uniformly distributed within a nucleus of radius R . The charge density (r) [charge per unit volume] is dependent only on the radial distance r from the centre of the nucleus as shown in figure. The electric field is only along the radial direction. Question: The electric field at r=R is

Options

  1. Aindependent of a
  2. Bdirectly proportional to a
  3. Cdirectly proportional to a^2
  4. Dinversely proportional to a

Correct answer

A. independent of a

Step-by-step solution

At r=R , from Gauss's law or aligned E (4 R^2 ) & = q_ net ₀ = Z e ₀ E & = 1 4 ₀ Z e R^2 aligned E is independent of ' a ' correct option is (a).

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