A capacitor consists of two charged disks of radius 4.5 m separated by a distanc
ID: 581352 • Letter: A
Question
A capacitor consists of two charged disks of radius 4.5 m separated by a distances s = 2 mm (see the figure). The magnitude of the charge on each disk is 56 meuC. Consider points A, B, C, and D inside the capacitor, as shown in the diagram. The distance s_1 = 1.2 mm, and the distance s_2 = 0.5 mm. (Assume the +x axis is to the right, the +y axis is up, and the +z axis is out.) What is the electric field inside the capacitor? First, calculate the potential difference V_B - V_A. What is delta l vector along this path? What is V_B - V_A? Next , calculate the potential difference V_C - V_B What is delta l vector along this path? What is V_C - V_B? Finally, calculate the potential difference V_A - V_C. What is delta l vector along this path? What is V_A - V_C?Explanation / Answer
a) E = Q/(A*epsilon)
= Q/(pi*r^2*epsilon)
= 56*10^-6/(pi*4.5^2*8.854*10^-12)
= 99420 N/c
b) vB - vA = E*s1
= 99420*1.3*10^-3
= 129.25 volts
delta_l = 1.3*10^-3 m
vB - vA = 129.25 volts
c) VC - VB = 0
delta_l = s2
= 0.5 mm
= 5*10^-4 m
Vc - VB = 0
d) VA - VC = vA - vB
= -129.25 volts
delta_l = sqrt(s1^2 + s2^2)
= sqrt(1.3^2 + 0.5^2)
= 1.393 mm
= 1.393*10^-3 m
vA - VC = -129.25 volts
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.