**2003**

**Common circuit for Questions 1 & 2:**

Assume that the switch S is in position 1 for a long time and thrown to position 2 at t=0.

1. At t = 0

^{+}, the current i

_{1}is

a) – V/2R

b) – V/R

c) – V/4R

d) Zero

2. I

_{1}(s) and I

_{2}(s) are the Laplace Transforms of i

_{1}(t) and i

_{2}(t) respectively. The equations for the loop currents I

_{1}(s) and I

_{2}(s) for the same circuit shown, after the switch is brought from position 1 to position 2 at t = 0, are

**2008**

3. In the following cirucit, the switch S is closed at t = 0. The rate of change of current di(0

^{+})/dt is given by

**Solution :**https://www.youtube.com/watch?v=WiYzbTZyhi0

**2009**

4. The switch in the circuit shown was on position 'a' for a long time, and is moved to position 'b' at time t=0. The current i(t) for t > 0 is given by

**Solution :**https://www.youtube.com/watch?v=ptI9Yzy17OQ

**2010**

5. In the cirucit shown, the switch S is open for a long time and is closed at t = 0. The current i(t) for t ≥ 0

^{+}is

**2011**

6. In the circuit shown below, the initial charge on the capacitor is 2.5 mC, with the voltage polarity as indicated. The switch is closed at time t = 0. The current i(t) at a time t after the switch is closed is

**2014**

7. In the figure shown, the ideal switch has been open for a long time.

If it is closed at t = 0, then the magnitude of the current (in mA) through the 4 kΩ resistor at t = 0

^{+}is ____________

**Solution :**https://www.youtube.com/watch?v=lr0Teo6g4nA

**2015**

8. In the circuit shown, the switch SW is thrown from position A to position B at time t=0. The energy (in µJ) taken from the 3 volts source to charge the 0.1 µF capacitor from 0 volts to 3 volts is

a) 0.3

b) 0.45

c) 0.9

d) 3

**Solution :**https://www.youtube.com/watch?v=ZbFt7Lkclp8

9. In the circuit shown, switch SW is closed at t =0. Assuming zero initial conditions, the value of V

_{c}(t) (in volts) at t = 1 sec is __________________

**Solution :**https://www.youtube.com/watch?v=_hcH81bC-cg