In one kind of computer keyboard each key is attached to a parallel plate capacitor as shown in the figure. The capacitor is maintained at a constant potential difference of 5V by an external circuit. When the key is pressed down, the top plate moves closer to the bottom plate, changing the capacitance and causing charge to flow through the circuit. If each plate is a square of side 6mm and the plate separation changes from 3mm to 1.2mm when a key is pressed, how much charge (in femto-Coulombs (10-15C)) flows through the circuit? Assume that there is air between the plates instead of dielectric. (Take eo = 9 x 10¬1ºF/m) Key. Answer: Movable plate- Dielectric Fixed plate-

In one kind of computer keyboard each key is attached to a parallel plate capacitor as shown in the figure. The capacitor is maintained at a constant potential difference of 5V by an external circuit. When the key is pressed down, the top plate moves closer to the bottom plate, changing the capacitance and causing charge to flow through the circuit. If each plate is a square of side 6mm and the plate separation changes from 3mm to 1.2mm when a key is pressed, how much charge (in femto-Coulombs (10-15C)) flows through the circuit? Assume that there is air between the plates instead of dielectric. (Take eo = 9 x 10¬1ºF/m) Key. Answer: Movable plate- Dielectric Fixed plate-

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter20: Electric Potential And Capacitance

Section: Chapter Questions

Problem 68P

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