The mass per unit length of a uniform wire is 0 . 135g cm ^ - 1 . A...

$\mu = 0 . 135gm{cm}^{- 1} = 0 . 0135kg{m}^{- 1}$

$y = - 0 . 21\sin \left(x + 30t\right)$

($x$ in meter & $t$ in sec)

$v = \dfrac{\omega}{k} = \dfrac{30}{1} = 30m{s}^{- 1}$

$v = \sqrt{\dfrac{T}{\mu}} ⇒ T = {v}^{2}\mu = {\left(30\right)}^{2}\left(0 . 0135\right)$

$= 12 . 15$

$= x \times {10}^{- 2}N$

$⇒ x = 1215$