A 10cmdiameter parallelplate capacitor has a 10 mm spacing T
A 10-cm-diameter parallel-plate capacitor has a 1.0 mm spacing. The electric field between the plates is increasing at the rate 1.0×106 V/ms .
What is the magnetic field strength on the axis? Express your answer to two significant figures and include the appropriate units.
What is the magnetic field strength 2.6 cm from the axis? Express your answer to two significant figures and include the appropriate units.
What is the magnetic field strength 7.2 cm from the axis? Express your answer to two significant figures and include the appropriate units.
Solution
I = e0 A dE/dt
A = pi (d/2)^2 = pi (0.10/2)^2 = 7.854 x 10^-3 m^2
dE/dt = 1 x 10^6 V / ms
I = (8.854 x 10^-12 ) ( 7.854 x 10^-3) (1 x 10^6 )
I = 6.954 x 10^-8 A
Integral of B.dL = u0 I
B ( 2 x pi x 0.026) = (4 x pi x 10^-7 ) (6.954 x 10^-8)
B = 5.35 x 10^-13 T ..........Ans
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for r = 7.2 cm
B = 1.932 x 10^-13 T
