A parallel plate capacitor with plate separation d is connected to a battery. Th

Question

A parallel plate capacitor with plate separation d 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). If none of the statements is correct, enter the word none.

A) With the capacitor connected to the battery, increasing d decreases Q.

B) After being disconnected from the battery, decreasing d increases U.

C) With the capacitor connected to the battery, inserting a dielectric with kappa > 1 will increase Q.

D) After being disconnected from the battery, inserting a dielectric with kappa > 1 will increase C.

E) With the capacitor connected to the battery, increasing d increases C.

F) With the capacitor connected to the battery, inserting a dielectric with kappa > 1 will increase U.

Explanation / Answer

(A)

True

becuas e

Q= CV = C ( E/d)

so increasing d decreasing Q

(B)

True

because

Charge Q is constant, energy stored is U = (0.5)Q2/C
Since C = A/d, increasing d causes C to decrease. Since C decreases, U then increases.

(c)

True

Q = CV =k A/d V

increasing capacitence increasing Q

(D)

True

(E)

False

C = A/d

increasing decresing C

(F)

True

energy stored is U = (0.5) CV^2
Since C = A/d, increasing k causes C to increases. so U then increases.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

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