A parallel plate capacitor with adjustible plate separation d and adjustible are

Question

1. A parallel plate capacitor with adjustible plate separation

d and adjustible area A is connected to a battery. The capacitor is fully charged to Q Coulombs and a voltage of V Volts. (C is the capacitance and U is the stored energy.) Give all correct answers concerning a parallel-plate capacitor charged by a battery (e.g. B, AC, CDF).

A) After being disconnected from the battery, decreasing d increases C.
B) After being disconnected from the battery, increasing the area A will decrease U.
C) With the capacitor connected to the battery, increasing the area A will increase Q.
D) With the capacitor connected to the battery, increasing d increases U.
E) With the capacitor connected to the battery, increasing the area A will increase C.
F) After being disconnected from the battery, increasing d increases V. I have tried: TTTFFT TTTFTT TFTFTT
Please explain, don't just give me the answer without explaination, Thanks! I have tried: TTTFFT TTTFTT TFTFTT
Please explain, don't just give me the answer without explaination, Thanks!

Explanation / Answer

You have to keep 2 points in mind while doing these type of problems.

1.when the capacitor is connected to battery ,the voltage across capacitor cannot change.

2.when it is disconnected ,the charge on the capacitor cannot change.

A)C is inversly proportional to d.So its true.

B)U=Q^2/2C and c is proportional to area.so its true(Q is constant)

C)Q=CV ,V is constant and C is proportional to area.so its true.

D)U=CV^2/2 ,V is constant and C is inversly proportional to d.so its false

E)true since C is proportional to area.

F)Q=CV,Q is constant so V is inversly proportional to C which implies it is proportional to d.So its true.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.