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Topic

Fourier Series

Asked 2 times in ESE, peaking in 2024.
2
PYQs
1
Exams
1
Years active
2024–2024
Span
2024
Peak
2/2
Answers
📅 Full chronological timeline →

Key insights

  • Most tested in ESE — 2 of 2 PYQs
  • Most asked in 2024
  • Recurs across 1 years (2024–2024)

Across exams

ESE · 2

How the concept evolved

224
Rising — more than half its appearances (2 of 2) are since 2016.

Sample questions

You've seen the pattern — here are a few of the actual PYQs.
ESE2024
The temperature distribution T(x) at a distance x, measured from one end, along a bar of length L is given by T(x) = Kx(L − x)(0 ≤ x ≤ L), where K = constant. A Fourier series expansion consisting of sine terms only for T(x) is
  1. A (8KL²/π³) Σ_{n=1}^∞ 1/(2n−1)³ sin (2n−1)πx/L ✓
  2. B (8KL²/π³) Σ_{n=1}^∞ 1/(2n−1)² sin (2n−1)πx/L
  3. C (8KL²/π³) Σ_{n=1}^∞ 1/(2n−1)³ sin (2n−1)πx/L
  4. D (8KL²/π³) Σ_{n=1}^∞ 1/(2n−1)² sin (2n−1)πx/L
✓ Correct answer: (A)
Engineering › Engineering Mathematics & General
ESE2024
Passing a sinusoidal voltage A sin ωt through a half-wave rectifier produces the clipped sine wave shown in the following figure. A Fourier series expansion of the rectified wave is
  1. A f(t) = (A/π)[1 + (π/2) sin ωt + 2 Σ_{n=1}^∞ cos 2nωt/(4n²−1)]
  2. B f(t) = (A/π)[1 + (π/2) sin ωt + 2 Σ_{n=1}^∞ cos 2nωt/(4n²−1)] ✓
  3. C f(t) = (A/π)[1 + (π/2) sin ωt − 2 Σ_{n=1}^∞ cos 2nωt/(4n²−1)]
  4. D f(t) = (A/π)[1 − (π/2) sin ωt + 2 Σ_{n=1}^∞ cos 2nωt/(4n²−1)]
✓ Correct answer: (B)
Engineering › Engineering Mathematics & General

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