A rod clamped in the middle has antinodes (A) at its ends and node (N) at the point of clamping. In fundamental mode, thus the length of the rod isWhere $l =$ length of rod and also $l =$ wavelength of the wave Here, $l = 100$ cm $\upsilon = 2.53 \text{ kHz} = 2.53 \times 10^3 \text{ Hz}$ ∴ $\lambda = 2 \times 100 = 200 \text{ cm}$ If $v$ be the speed of sound in steel, then $v = \upsilon \lambda = 2.53 \times 10^3 \times 200$ $= 506 \times 10^3 \text{ cm s}^{-1}$ $= 5.06 \times 103 \text{ ms}^{-1}$ $v = 5.06 \text{ km s}^{-1}.$