Question

A current of [2 + \sqrt{2}sin (314t + 30) + 2\sqrt{2}cos (952t +45)] is measured with a thermocouple type, 5A full scale, class 1 meter. The meter reading would lie in the range? (a) 5 A ± 1 % (b) (2 + 3\sqrt{2}) A ± 1% (c) 3 A ± 1.7 % (d) 2 A ± 2.5 % I have been asked this question in an interview for job. The doubt is from Advanced Problems on Magnetically Coupled Circuits in section Resonance & Magnetically Coupled Circuit of Network Theory Select the correct answer from above options network theory questions and answers, network theory questions pdf, network theory question bank, network theory gate questions and answers pdf, mcq on network theory pdf, gate network theory questions and solutions, network theory mcq Test , ies network theory questions, Network theory Questions for GATE EC Exam, Network Theory MCQ (Multiple Choice Questions)

Answer 1

Correct option is (c) 3 A ± 1.7 % The explanation: I = [2 + \sqrt{2} sin (314t +30°) + 2\sqrt{2} cos (952t + 45°)] Thermocouple measure the rms value of current. Irms = \Big[2^2 + \left(\frac{\sqrt{2}}{\sqrt{2}}\right)^2 + \left(\frac{2\sqrt{2}}{\sqrt{2}}\right)^2\Big]^{1/2} = \sqrt{9} = 3 A ± 1.7%.