The angular frequency, \omega, of a wave is related to the wave vector, k, by the relation \omega = \omega_{0} \sin\frac{ka}{2} \text{ for } 0 < k > \frac{\pi}{a} Determine the phase and group velocities of this wave and draw a rough sketch to show their variation with k(0 < k < \pi/a)
481cse-1986-subject-02-003
Paper I20 Marks
482cse-1986-subject-02-002
Paper I20 Marks
Out of the following three functions only one can be Fourier analysed in the range -\pi \leqslant x \leqslant \pi. Choose the correct function and obtain its Fourier series expansion: (i) f(x) = x^{2} \text{ for } 0 < x < \pi (ii) f(x) = 0 \text{ for } -\pi < x < 0 = \pi \text{ for } 0 < x < \pi (iii) f(x) = 1/x^{2} \text{ for } -\pi < x < \pi
483cse-1986-subject-02-006
Paper I20 Marks
Define and explain the terms resolving power and magnifying power of an optical instrument. For a telescope, on that parameter do these depend? For a given resolving power, what is the optimum magnifying power?