A commercial capacitor is constructed as in Figure 16.25a. This particular capac

Question

A commercial capacitor is constructed as in Figure 16.25a. This particular capacitor is made from a strip of aluminum foil separated by two strips of paraffin-coated paper. Each strip of foil and paper is 8.00 cm wide. The foil is 0.00400 mm thick, and the paper is 0.025 mm thick and has a dielectric constant of 3.7. What length should the strips be if a capacitance of 9.00 10-8 F is desired before the capacitor is rolled up? (Use the parallel-plate formula. Adding a second strip of paper and rolling up the capacitor doubles its capacitance by allowing both surfaces of each strip of foil to store charge.)
1 m

Explanation / Answer

Assume it to be parallel plate capacitor

Capacitance of a parallel plate capacitor, C = kAe/d
A = 0.08*l ( l is length of the strip)
e = 8.854 * 10 ^ -12
d = 2*0.025*10^-3
Doubling the ccapacitance as giben

C = 3.7*14.1664 * 10 ^-9 * l *2= 90*10^-9
l = 1.717 m

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

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