Problem: The switch in the figure has been in position a for a long time. It is changed to position b at t=0s.a) What is the charge Q on the capacitor immediately after the switch is closed?b) What the current I through the resistor immediately after the switch is closed?c) What is the charge Q on the capacitor at t=50 × 10-6 s?d) What is the current I through the resistor at t=50 × 10-6 s?e) What is the charge Q on the capacitor at t=200 × 10-6 s?f) What is the current I through the resistor at t=200 × 10-6 s?

FREE Expert Solution

The charge stored in a capacitor:

$\boxed{\mathbf{Q}\mathbf{=}\mathbf{C}\mathbf{V}}$

Ohm's law:

$\boxed{\mathbf{V}\mathbf{=}\mathbf{I}\mathbf{R}}$

Charge in capacitor after sometime:

$\boxed{\mathbf{Q}\mathbf{=}{\mathbf{Q}}_{\mathbf{0}}{\mathbf{e}}^{\mathbf{(}\mathbf{-}\mathbf{t}\mathbf{/}\mathbf{R}\mathbf{C}\mathbf{)}}}$

(a) 
Q = CV = 4 × 10^-6 × 9 = 36 × 10^-6 C

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