GATE EC 2019 Set 1 — Question 14
Go beyond PYQs with Success TrackerAI-powered personalised practice and doubt support. Unlimited practice on eligible plans; AI usage limits apply.MCQ+1 / -0.33EasyReciprocity TheoremCircuit Fundamentals & TheoremsNetwork Theory
Network Theory → Circuit Fundamentals & Theorems → Reciprocity Theorem
Last updated
Question
Consider the two-port resistive network shown in the figure. When an excitation of is applied across Port 1, and Port 2 is shorted, the current through the short circuit at Port 2 is measured to be (see (a) in the figure).
Now, if an excitation of is applied across Port 2, and Port 1 is shorted (see (b) in the figure), what is the current through the short circuit at Port 1?
Now, if an excitation of is applied across Port 2, and Port 1 is shorted (see (b) in the figure), what is the current through the short circuit at Port 1?

Correct answer
(B) 1 A
Solution
According to the Reciprocity Theorem, for a linear, passive, and bilateral network, the ratio of excitation to response remains constant even if the positions of excitation and response are interchanged. In case (a):
Excitation at Port 1
Response at Port 2 (short-circuited)
Transfer conductance In case (b):
Excitation at Port 2
Response at Port 1 (short-circuited)
By reciprocity,
.
Excitation at Port 1
Response at Port 2 (short-circuited)
Transfer conductance In case (b):
Excitation at Port 2
Response at Port 1 (short-circuited)
By reciprocity,
.
Continue learning with Success Tracker
A step still unclear? Work through it with support
Use Success Tracker to ask about the reasoning, then try another GATE EC question to check your understanding.
AI-powered practice· Unlimited practice on eligible plans
- PYQs with solutions
- Attempt available previous-year questions, then compare your reasoning with the worked solution. Coverage varies by stream.
- Practice that adapts
- Choose a topic, work on weaker areas and bookmark questions to revisit. Your attempts feed your progress tracking.
- AI doubt support
- Ask follow-up questions about a step or concept while practising, instead of stopping at the final answer.
Unlimited practice is available on eligible plans. Free practice and AI usage have limits; check the current plan allowances before choosing.
This page stays readable without an account. AI responses can be wrong; check them against the solution and source material.
More questions on Circuit Fundamentals & Theorems
2026 Set 1 Q23The relation between the input current () and the output voltage () of a circuit is governed…2026 Set 1 Q30The output voltage (in Volt) for the network given in the Figure is __. (rounded off to two…2026 Set 1 Q31Consider the circuit shown in the Figure, where the input is in Volt. The average power…2026 Set 1 Q39In the given circuit, and . The phasor diagram for and…2026 Set 1 Q51Consider the two-port network as shown in the Figure. Which of the following options provides the…