MCQ
The dielectric constant K of an insulator will be-
- A0.4
- B4
- C-4
- D$0$
✓
Answer
(b) 4
Explanation: Dielectric constant of air is 1. All dielectrics generally have a value of the dielectric constant greater than 1. $K=\frac{F}{F_m}$
where Fm is the force between two charged particles in a medium of dielectric constant K and F is the force between the two charges when placed in air.The force between two charges is greatest in air or vacuum and it decreases when any medium is placed between the charges. K cannot have negative, fractional or zero values.
Explanation: Dielectric constant of air is 1. All dielectrics generally have a value of the dielectric constant greater than 1. $K=\frac{F}{F_m}$
where Fm is the force between two charged particles in a medium of dielectric constant K and F is the force between the two charges when placed in air.The force between two charges is greatest in air or vacuum and it decreases when any medium is placed between the charges. K cannot have negative, fractional or zero values.
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