Consider the following statements regarding Dielectrics:1.Dielectric materials reduce electric field within them due to polarization effects.2.Relative permittivity is always greater than or equal to unity for dielectric materials.3.Polarization results from alignment of dipoles within the material.4.Dielectrics increase capacitance by increasing electric field strength.Which of the above statements is/are correct?

Correct Answer: C - 1, 2 and 3 only

Quick Concept Explanation

Bound charges created by polarization oppose the applied field inside the material and increase capacitance for a fixed geometry. Relative permittivity is the ratio ε/ε0 and is at least unity for ordinary passive dielectrics in elementary electrostatics. Key relation: C=εA/d=ε_r ε₀A/d.

Exam focus: Higher permittivity raises capacitance; it does not do so by increasing the internal electric field. Common trap: Do not confuse increased capacitance with increased field strength.

Statement-wise Verification

• Statement 1 - Correct.
  Dielectric materials reduce electric field within them due to polarization effects.
  A dielectric polarizes in an electric field.
• Statement 2 - Correct.
  Relative permittivity is always greater than or equal to unity for dielectric materials.
  Relative permittivity is the ratio ε/ε0 and is at least unity for ordinary passive dielectrics in elementary electrostatics.
• Statement 3 - Correct.
  Polarization results from alignment of dipoles within the material.
  Bound charges created by polarization oppose the applied field inside the material and increase capacitance for a fixed geometry.
• Statement 4 - Incorrect.
  Dielectrics increase capacitance by increasing electric field strength.
  A dielectric increases capacitance through higher permittivity/polarization; for fixed free charge it reduces the internal field

Core Concept

A dielectric polarizes in an electric field. Bound charges created by polarization oppose the applied field inside the material and increase capacitance for a fixed geometry. Relative permittivity is the ratio ε/ε0 and is at least unity for ordinary passive dielectrics in elementary electrostatics.

Formula / Key Relationship

C=εA/d=ε_r ε₀A/d.

Why the Other Options Are Wrong

Option A is incorrect because it omits correct statement(s) 1. Option B is incorrect because it includes incorrect statement(s) 4 and omits correct statement(s) 2, 3. Option D is incorrect because it includes incorrect statement(s) 4.

Exam Shortcut / Approach

Higher permittivity raises capacitance; it does not do so by increasing the internal electric field.

Common Mistake

Do not confuse increased capacitance with increased field strength.

Quick Revision

Permittivity Polarization and Capacitance is linked with Polarization, Dielectrics and Electromagnetic Fields. Higher permittivity raises capacitance; it does not do so by increasing the internal electric field.