A parallel plate capacitor is charged from a cell and then isolated from it. The separation between the plates is now increaseda)The force of attraction between the plates will decreaseb)The energy stored in the capacitor will increasec)The potential difference between the plates will decreased)The field in the region between the plates will not changeCorrect answer is option 'B,D'. Can you explain this answer?

Question

Answer

Explanation:
When a parallel plate capacitor is charged from a cell and then isolated from it, several changes occur. Let's examine each option individually:

A) The force of attraction between the plates will decrease:
The force of attraction between the plates of a capacitor is given by the equation F = (Q^2) / (2εA), where Q is the charge on the plates, ε is the permittivity of the medium between the plates, and A is the area of the plates. The force of attraction is directly proportional to the charge on the plates. Therefore, when the separation between the plates is increased, the charge on the plates remains constant, and the force of attraction between the plates decreases. So, option A is correct.

B) The energy stored in the capacitor will increase:
The energy stored in a capacitor is given by the equation U = (1/2) (Q^2) / C, where U is the energy stored, Q is the charge on the plates, and C is the capacitance of the capacitor. The energy stored is directly proportional to the square of the charge on the plates. When the separation between the plates is increased, the capacitance of the capacitor decreases according to the equation C = (εA) / d, where ε is the permittivity of the medium between the plates and d is the separation between the plates. As the capacitance decreases, the energy stored in the capacitor increases. So, option B is correct.

C) The potential difference between the plates will decrease:
The potential difference between the plates of a capacitor is given by the equation V = Q / C, where V is the potential difference, Q is the charge on the plates, and C is the capacitance of the capacitor. When the separation between the plates is increased, the capacitance of the capacitor decreases, as mentioned earlier. As a result, the potential difference between the plates also decreases according to the equation V = Q / C. So, option C is correct.

D) The electric field in the region between the plates will not change:
The electric field between the plates of a capacitor is given by the equation E = V / d, where E is the electric field, V is the potential difference between the plates, and d is the separation between the plates. When the separation between the plates is increased, the potential difference between the plates decreases, but the separation also increases proportionally. As a result, the electric field between the plates remains constant. So, option D is correct.

In conclusion, the correct options are B and D: The energy stored in the capacitor will increase, and the electric field in the region between the plates will not change.

Answer

The correct answers are: The field in the region between the plates will not change, The energy stored in the capacitor will increase

Similar Physics Doubts

The plates of a parallel plate capacitor with no dielectric are connected to a voltage source. Now a dielectric of dielectric constantKis inserted to fill the whole space between the plates with voltage source remaining connected to the capacitor.

A parallel plate capacitor is charged and then the battery is disconnected. When the plates of the capacitor are brought closer, then

A capacitor of capacitance 10µFis charged to a potential of 100V. Now connecting it in parallel with an uncharged capacitor, the resultant potential difference becomes 40volt. The capacitance of this capacitor (inµF) is. Correct answer is '15'. Can you explain this answer?

A battery of internal resistance 2Ω is connected to a variable resistor whose value can vary from 4Ω to 10Ω. The resistance is initially set at 4Ω. If the resistance is now increased then, which of the statement is not correct.

Top Courses for Physics

Suggested Free Tests

Related Content

Schools

Competitive Examinations

Quick Access Links

Technical Exams