For a particular tube, among six harmonic frequencies below 1000 Hz, only four harmonic frequencies are given: 300 Hz, 600 Hz, 750 Hz and 900 Hz. What are the two other frequencies missing from this list?

(a)

100 Hz, 150 Hz

(b)

150 Hz, 450 Hz

(c)

450 Hz, 700 Hz

(d)

700 Hz, 800 Hz

Compare the velocities of the wave forms given below, and choose the correct option.

where, v_A, v_B, v_C and v_D are velocities given in (A), (B), (C) and (D), respectively.

(a)

v_A > v_B > v_D > v_C

(b)

v_A< v_B < v_D < v_C

(c)

v_A = v_B = v_D = v_C

(d)

v_A > v_B = v_D > v_C

A person standing between two parallel hills fires a gun and hears the first echo after t₁ sec and the second echo after t₂ sec. The distance between the two hills is

(a)

\(\frac { v({ t }_{ 1 }-{ t }_{ 2 }) }{ 2 } \)

(b)

\(\frac { v\left( { t }_{ 1 }{ t }_{ 2 } \right) }{ 2({ t }_{ 1 }+{ t }_{ 2 }) } \)

(c)

v (t₁ + t₂)

(d)

\(\frac { v({ t }_{ 1 }+{ t }_{ 2 }) }{ 2 } \)

The displacement y of a wave travelling in the x direction is given by y = (2\(\times\)10 ^-3) sin (300t - 2x + \(\frac{\pi}{4}\)), where x and y are measured in metres and t in second. The speed of the wave is

(a)

150 ms^-1

(b)

300 ms^-1

(c)

450 ms^-1

(d)

600 ms^-1

Which of the following represents a wave

(a)

(x - vt)³

(b)

x(x+vt)

(c)

\(\frac{1}{x+vt}\)

(d)

sin(x+vt)