[PHYS] Example Question: In the circuit of the figure below, the switch S has been open for a long time. It is then suddenly closed. Take e m f = 10.0 V, R1 = 42.0 kΩ, R2 = 120 kΩ, and C = 12.0 𝜇F.

Example Question

---

 

# Question

In the circuit of the figure below, the switch S has been open for a long time. It is then suddenly closed. Take  E = 10.0 V, R1 = 42.0 kΩ, R2 = 120 kΩ, and C = 12.0 𝜇F.

Determine the time constant before the switch is closed.

 Determine the time constant after the switch is closed.

Let the switch be closed at t = 0. Determine the current in the switch as a function of time. (Assume I is in A and t is in s. Do not enter units in your expression. Use the following as necessary: t.)

---

# Explanation

Determine the time constant before the switch is closed.

 

 Determine the time constant after the switch is closed.

 

Let the switch be closed at t = 0. Determine the current in the switch as a function of time. (Assume I is in A and t is in s. Do not enter units in your expression. Use the following as necessary: t.)

---