Question

Two identical strings X and Z made of same material have tension T_X and T_Z in then If their fundamental frequencies are 450 Hz and 300 Hz, respectively, then the ratio T_X/T_Z is : 

(1) 1.25 

(2) 0.44 

(3) 1.4 

(4) 2.25

Comments

Chapter simple harmonic motion (SHM)

Answer 1

Ans. (4) 2.25

Sol. $f_x={1\over2l}\sqrt{T_x\over\mu}$

$f_z={1\over2l}\sqrt{T_z\over\mu}$

${f_x\over f_z}={450\over300}=\sqrt{T_x\over T_z}$

$\implies T_x/T_z = 9/4 = 2.25$

Comments

it should be 9/6 na...as 50*6=300