1. Consider the figure shown below. Find the voltage (V) at node 2.
a) 11.5
b) 12
c) 12.5
d) 13
Explanation: The equation at node 1 is 10 = V1/3+(V1-V2)/2
According to super Node analysis, (V1-V2)/2=V2/1+(V3-10)/5+V3/2V2-V3=20. On solving, we get, V2=11.5V.
2. Find the voltage (V) at node 3 in the figure shown below.
a) 18
b) 20
c) 22
d) 24
Explanation: At node 1, (V1-40-V3)/4+(V1-V2)/6-3-5=0. Applying Super Node Analysis at node 2 and 3, (V2-V1)/6+5+V2/3+V3/5+(V3+40-V1)/4=0. Also, V3-V2=20. On solving above equations, V3 = 18.11V ≈ 18V.
3. Find the power absorbed by 5Ω resistor in the following figure.
a) 60
b) 65.5
c) 70.6
d) 75
Explanation: The current through 5Ω resistor = V3/5=18.11/5=3.62A. The power absorbed by 5Ω resistor = (3.62)2)×5=65.52W.
4. Find the value of the voltage (V) in the equivalent voltage source of the current source shown below.
a) 20
b) 25
c) 30
d) 35
Explanation: The value of the voltage (V) in the equivalent voltage source of the current source the voltage across the terminals A and B is (6)(5) = 30V.
5. Find the value of the current (A) in the equivalent current source of the voltage source shown below.
a) 1
b) 2
c) 3
d) 4
Explanation: The value of the current (A) in the equivalent current source of the voltage source the short circuit current at the terminals A and B is I=60/30=2A.
6. Pick the incorrect statement among the following.
a) Inductor is a passive element
b) Current source is an active element
c) Resistor is a passive element
d) Voltage source is a passive element
Explanation: Energy sources(voltage or current sources) are active elements, capable of delivering power to some external device.
7. For a voltage source to be neglected, the terminals across the source should be ___________
a) replaced by inductor
b) short circuited
c) replaced by some resistance
d) open circuited
Explanation: If the voltage source is to be neglected, it can be replaced simply by means of a wire i.e, it should be short circuited.
8. Voltage source and terminal voltage can be related as ___________
a) terminal voltage is higher than the source emf
b) terminal voltage is equal to the source emf
c) terminal voltage is always lower than source emf
d) terminal voltage cannot exceed source emf
Explanation: A practical voltage source can be represented with a resistance in series with the source. Hence, there would be some voltage drop at the resistor and the terminal voltage is always lower than the source emf.
9. In case of ideal current sources, they have ___________
a) zero internal resistance
b) low value of voltage
c) large value of currrent
d) infinite internal resistance
Explanation: For the ideal current sources, the current is completely independent of voltage and it has infinte internal resistance.
10. In a network consisting of linear resistors and ideal voltage source, if the value of resistors are doubled, then voltage across each resistor ___________
a) increases four times
b) remains unchanged
c) doubled
d) halved
Explanation: Even on changing the values of linear resistors, the voltage remains constant in case of ideal voltage source.