Parallel Networks MCQ (Interview-Exam) Question-Answer
Q.1 Calculate the current across the 20 ohm resistor.
A. 20A
B. 36.67A
C. 10A
D. 6.67A
Ans : 10A
Explanation: I=V/R. Since in parallel circuit, voltage is same across all resistors. Hence across the 20 ohm resistor, V=200V so I=200/20=10A.
Q.2 If two bulbs are connected in parallel and one bulb blows out, what happens to the other bulb?
A. The other bulb continues to glow with the same brightness
B. The other bulb stops glowing
C. The other bulb blows out as well
D. The other bulb glows with increased brightness
Ans : The other bulb continues to glow with the same brightness
Q.3 The current in each branch of a parallel circuit is proportional to _________
A. Proportional to the value of the resistors
B. Proportional to the power in the circuit
C. The amount of time the circuit is on for
D. Equal in all branches
Ans : Proportional to the value of the resistors
Q.4 In a parallel circuit, with a number of resistors, the voltage across each resistor is ________.
A. Is divided equally among all resistors
B. Is zero for all resistors
C. The same for all resistors
D. Is divided proportionally across all resistors
Ans : The same for all resistors
Q.5 The voltage across the open circuit is?
A. Infinity
B. 0V
C. 100V
D. 90V
Ans : 100V
Explanation: The voltage across all branches in a parallel circuit is the same as that of the source voltage. Hence the voltage across the 10 ohm resistor and the open circuit is the same=100V.
Q.6 Calculate the total current in the circuit.
A. 10 A
B. 15 A
C. 20 A
D. 11.43 A
Ans : 11.43 A
Explanation: The 1 ohm and 2 ohm resistor are in series which is in parallel to the 3 ohm resistor. The equivalent of these resistances (3/2 ohm) is in series with the 4 ohm and 5 ohm resistor. Total R = 21/2 ohm. I=V/R=120/(21/2)=240/21=11.43 A.
Q.7 If the current through x ohm resistance in the circuit is 5A, find the value of x.
A. 5 ohm
B. 135 ohm
C. 27 ohm
D. 12 ohm
Ans : 27 ohm
Explanation: R=V/I. In this circuit I=5A and V=135V. Therefore, R=135/5=27 ohm.
Q.8 The voltage across the short is?
A. Infinity
B. 11.25V
C. 135V
D. Zero
Ans : Zero
Explanation: The voltage across a short is always equal to zero whether it is connected in series or parallel.
Q.9 The total resistance between A and B are?
A. 5 ohm
B. 0 ohm
C. 20 ohm
D. 80 ohm
Ans : 5 ohm
Explanation: I=V/R. Total resistance R = 20+40=60ohm. V=120V. I=120/60=2A.
Q.10 The currents in the three branches of a parallel circuit are 3A, 4A and 5A. What is the current leaving it?
A. Insufficient data provided
B. 12A
C. 0A
D. The largest one among the three values
Ans : 12A
Parallel Networks in Electrical Engineering
1. Redundancy and Reliability:
- One of the primary purposes of parallel networks is to enhance system reliability. If one path or component fails, the system can continue to operate using an alternative path.
- Redundancy in parallel networks helps in minimizing the impact of component failures, ensuring continuous operation and reducing downtime.
2. Load Sharing and Balancing:
- Parallel networks allow for load sharing among multiple paths or components. This helps in distributing the workload evenly, preventing overloading of any single element.
- Load balancing ensures optimal utilization of resources and improves the overall efficiency of the system.
3. Performance Improvement:
- Parallel networks can be used to enhance the performance of a system by allowing multiple operations to occur simultaneously.
- In data processing and communication systems, parallel processing can lead to faster data transmission and reduced latency.
4. Scalability:
- Parallel networks provide scalability by allowing the addition of more components or paths to handle increased loads or requirements.
- This scalability is beneficial in various applications, such as cloud computing and data centers.
5. Fault Tolerance:
- Parallel networks contribute to fault tolerance by providing alternative routes or components in case of faults or errors.
- This feature is crucial in critical systems where continuous operation is essential, such as in power distribution networks and mission-critical communication systems.
6. Power Distribution Systems:
- In power distribution systems, parallel networks are used to ensure reliable and continuous power supply. Multiple lines or circuits are employed to distribute electrical power to consumers.
- This configuration allows for rerouting power in case of faults or maintenance activities, minimizing disruptions.
7. Communication Networks:
- Telecommunication networks often employ parallel paths to ensure reliable and efficient data transmission. Multiple communication channels help in maintaining connectivity and preventing data loss.
8. Computing Systems:
- Parallel computing involves the simultaneous execution of multiple tasks to improve computational efficiency. Parallel networks in computing systems enable faster processing and better utilization of resources.
9. Research and Development:
- Parallel networks are extensively used in research and development, particularly in simulation and modeling tasks. Parallel processing accelerates complex calculations and simulations, saving time and resources.
10. Cost Considerations:
- While parallel networks offer numerous benefits, there are also cost considerations associated with the implementation of redundant components and infrastructure.
- Designing a cost-effective parallel network requires a balance between redundancy, reliability, and the overall cost of the system.