Q. If the speed of the wave shown in the figure is $330m/s$ in the given medium, then the equation of the wave propagating in the positive $x$-direction will be (all quantities are in M.K.S. units)
A) $y = 0.05\sin{2\pi(4000\ t - 12.5\ x)}$
B) $y = 0.05\sin{2\pi(4000\ t - 122.5\ x)}$
C) $y = 0.05\sin{2\pi(3300\ t - 10\ x)}$
D) $y = 0.05\sin{2\pi(3300\ x - 10\ t)}$
Explanation
(c) Here $A = 0.05m,\frac{5\lambda}{2} = 0.25 \Rightarrow \lambda = 0.1m$
Now standard equation of wave
$y = A\sin\frac{2\pi}{\lambda}(vt - x)$
$\Rightarrow y = 0.05\sin{2\pi(3300t - 10x)}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.