The capacity of a parallel plate capacitor is 5µF. When a glass plate is placed between the plates of the capacitor, its potential becomes1/8 of the orignal value. The value of dielectric constant will be
Correct answer: B. 8
- A. 1.6
- B. 8
- C. 5
- D. 40
Explanation
The dielectric constant (K) of a material inserted between the plates of a capacitor is defined as the ratio of the original potential (V0) to the new potential (V) when the dielectric is present: K = V0/V. Here, V becomes 1/8 of the original potential, which means K = 8. Therefore, the dielectric constant is 8.Option A (1.6) is incorrect, as it underestimates the effect of the dielectric. Option C (5) is misleading because it might be mistaken for the capacitance value. Option D (40) is too large and not supported by the observed change in potential.
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Electrostatics describes forces between charges through Coulomb's law, electric fields and field intensity, then uses electric potential to measure energy per unit charge. Capacitors store charge and electrical energy, with capacitance depending on geometry and dielectric material, not simply on the amount of charge present.
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