The capacity of a condenser in which a dielectric of dielectric constant 5 has been used, is C. If the dielectric is replaced by another with dielectric constant 20, the capacity will become:
Correct answer: C. 4C
- A. C/4
- B. C/2
- C. 4C
- D. 2C
Explanation
Capacitance is directly proportional to the dielectric constant (k). The ratio of the new capacitance (C') to the old (C) is equal to the ratio of the dielectric constants: C'/C = k'/k = 20/5 = 4. Therefore, the new capacity will be 4C.
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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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