Unformatted text preview: 49. (a) With the potential diﬀerence equal to 600 V, a capacitance of 2.5 × 10−10 F can only store energy
equal to U = 1 CV 2 = 4.5 × 10−5 J.
(b) No, our result from part (a) is only about 20% of that needed to produce a spark.
(c) Considering the charge as a constant, then voltage should be inversely proportional to the capacitance. Therefore, if the capacitance drops by a factor of ten, then we expect the voltage to increase
by that same factor: Vf = 6000 V.
(d) Now the energy stored is U =
obtained in part (a). 1
2 Cf Vf = 4.5 × 10−4 J, a factor of ten greater than the value we (e) Yes, this new value of energy is nearly double that needed for a spark. ...
View Full Document