KVPY2017PhysicsWaves and Sound
A transverse wave of frequency 500 ~Hz and speed 100 ~m / s is traveling in the positive x direction on a long string. At time t =0 ~s the displacements at x=0.0 ~m and at x =0.25 ~m are 0.0 ~m and 0.02 ~m , respectively. The displacement at x =0.2 ~m at t =5 10⁻⁴ ~s is
Options
- A-0.04 ~m
- B-0.02 ~m
- C0.04 ~m
- D0.02 ~m
Correct answer
B. -0.02 ~m
Step-by-step solution
y = A ( kx - t ) at x =0.025, y =0.02 v = v = 100 500 = 1 5 ~m y =0.02= A ( 2 1 4 ) y =0.002= A ( 5 2 ) A =0.02 ~m y =0.02 ( kx - t ) =0.02 (10 0.2-1000 5 10⁻⁴ ] =0.02 [2 -0.5 ] =0.02 ( 3 2 )=-0.02 ~m