In one type of computer keyboard, each key holds a small metal plate that serves as one plate of a parallel-plate, air-filled capacitor. When the key is depressed, the plate separation decreases and the capacitance increases. Electronic circuitry detects the change in capacitance and thus detects that the key has been pressed. In one particular keyboard, the area of each metal plate is 43.5 mm. and the separation between the plates is 0.710 mm before the key is depressed. Part A Calculate the capacitance before the key is depressed. Ινα ΑΣφ ? C = F Submit Request Answer • Part B If the circuitry can detect a change in capacitance of 0.220 pF. how far must the key be depressed before the circuitry detects its depression? h = mm Submit Reguest Answer

In one type of computer keyboard, each key holds a small metal plate that serves as one plate of a parallel-plate, air-filled capacitor. When the key is depressed, the plate separation decreases and the capacitance increases. Electronic circuitry detects the change in capacitance and thus detects that the key has been pressed. In one particular keyboard, the area of each metal plate is 43.5 mm. and the separation between the plates is 0.710 mm before the key is depressed. Part A Calculate the capacitance before the key is depressed. Ινα ΑΣφ ? C = F Submit Request Answer • Part B If the circuitry can detect a change in capacitance of 0.220 pF. how far must the key be depressed before the circuitry detects its depression? h = mm Submit Reguest Answer

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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