Question

The following two questions refer to the circuit shown. Assume that the capacitors are initially uncharged.

At time t = 0, the switch S in the circuit is closed. At that instant, what is the equivalent resistance of the circuit?
A. `9.00`
B. `1.20`
C. `1.80`
D. `0.92`

Answer 1

Correct Answer - D
Initially capacitors act as conducting wire. So initially all the three resistor will be in parallel.
After long time, resistors will be in series,
`R_(eq) = 2+3+4 =9Omega`
`I = (24)/(9) = (8)/(3)A`
Potential difference `3muF =` potential difference across `(3Omega+4Omega)`
`rArr V_(3muF) = (3 +4)I = (56)/(3)v`
`q = CV_(3muF) = (3xx56)/(3) = 56muC`