What is the electric field strength inside the capacitor? What is the potential energy of a proton at the midpoint of the capacitor?
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Answer:
2.4*10^-17 J
Explanation:
E = V/d = 300 V / 3*10^-3 m = 1.0*10^5 V/m
Voltage at midpoint = E*d = 1.0*10^5 V/m * 1.5*10^-3 m = 150 V
ΔV = 300 V - 150 V = 150 V
Charge of a proton = 1.6*10^-16 C
U = qΔV = (1.6*10^-16 C)(150V) = 2.4*10^-17 J