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KVPY2017PhysicsElectrostatics

Let the electrostatic field E at distance r from a point charge q not be an inverse square but, instead an inverse cubic, e.g. E = k q r ³ r Here k is a constant. Consider the following two statements (i) Flux through a spherical surface enclosing the charge is =q_ enclosed / ₀ (ii) A charge placed inside uniformly charged shell will experience a force. Choose the correct option.

Options

  1. AOnly (i) is valid
  2. BOnly (ii) is valid
  3. CBoth (i) and (ii) are invalid
  4. DBoth (i) and (ii) are valid

Correct answer

B. Only (ii) is valid

Step-by-step solution

| E |= kq r ³ d = E dS = d = E dS = kq r ³ 4 r ² = kq 4 r q _ en ₀ force on q^ is zero

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