Question

The equation of travelling wave is, $y(x,t)=0.02sin\left(\frac{x}{0.05}+\frac{t}{0.01}\right)m$
Find:

The particle velocity at $x=0.2m$ and $t=0.3s$.
Given $cos\theta =-0.85$
where $\theta =34$ rad

• A. $-1.7m/s$
• B. $-2.7m/s$
• C. $-3.7m/s$
• D. $-6.7m/s$

Answer 1

The correct option is A $-1.7m/s$

The equation of a left travelling wave is of form $y=Asin(kx+\omega t)$

Thus velocity of each particle would be given by $\frac{dy}{dt}=A\omega cos(kx+\omega t)$

Particle velocity at given position and time $=\frac{0.02}{0.01}cos(\frac{0.2}{0.05}+\frac{0.3}{0.01})=-1.7m/s$