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Question
In a parallel plate capacitor with air between the plates, each plate has an area of 6 × 10−3 m2 and the distance between the plates is 3 mm. Calculate the capacitance of the capacitor. If this capacitor is connected to a 100 V supply, what is the charge on each plate of the capacitor?
Solution
Given, plate area A = 6 × 10-3 m2, V = 100 volts
Distance between the poles d = 3 mm = 3 × 10-3 m
Capacitance C = ?, Charge on each strip = ?
Formula, Capacitance (C) = `(ε_0 "A")/"d"`
= `(8.854 xx 10^-12 xx 6 xx 10^-3)/(3 xx 10^-3)`
= 17.7 × 10-12
Charge on capacitor q = C × V
= 17.7 × 10-12 × 100
= 17.7 × 10-10 C
∴ Charge on one strip = + 17.7 × 10-10 C
Charge on the second strip = - 17.7 × 10-10 C
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