Two round disks, each with a 0.5 cm diameter are spaced 2 mm apart. Batman conne

Question

Two round disks, each with a 0.5 cm diameter are spaced 2 mm apart. Batman connects these two disks to opposite terminals of a compact 65,000 V experimental battery he has borrowed from Stark Industries, and thus forms a powerful capacitor. Batman then disconnects this battery, leaving the plates of his capacitor charged.

What basic equation should you use to find the capacitance between these disks?

What values should be used for each of you variables?

Now, solve to find the capacitance of the two disks Batman has applied a voltage to!

The capacitance of the two disks is _________________?

What basic equation should you use to find the charge on the capacitor?

What values should be used for each of your variables?

Now, solve to find the charge on Batman

Explanation / Answer

V = 65000 V

diameter = 0.5 cm

So, radius, r = 0.25 cm = 0.0025 m

distance between the two plates, d = 2mm = 0.002 m

Capacitance of the capacitor, C = eA/d

where e = permittivity of free space = 8.854*10^-12

A = area of the plates = pi*r^2 = pi*0.0025^2 = 1.96*10^-5 m2

d = 0.002 m

So, C = 8.854*10^-12*1.96*10^-5/(0.002) = 8.68*10^-14 F <-------------answer

Charge on the capacitor,

Q = C*V

C = 8.68*10^-14 F

V = 65000 V

Charge , Q =  8.68*10^-14*65000

= 5.64*10^-9 C <---------------answer

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

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