Question

The rope shown at an instant is carrying a wave travelling towards right, created by a source vibrating at frequency n Hz. Here a, b, c, d and e are x co-ordinates. Choose the correct statement(s)

• A. The speed of the wave is 4n $\times$ (b – a)
• B. The particle at x = a will be in the same phase as particle at x = d after $\frac{4}{3n}$ sec.
• C. The phase difference between particles at x = b and x = e is $\frac{3\pi }{2}$
• D. Particles at x = a and x = e vibrate in same phase

Answer 1

Answer: (A), (C)

The correct options are
A

The speed of the wave is 4n $\times$ (b – a)

C

The phase difference between particles at x = b and x = e is $\frac{3\pi }{2}$

$v=\frac{\omega }{k}=\frac{2\pi n}{\frac{2\pi }{\lambda }}=n\lambda ;\frac{\lambda }{4}=(b-a),\lambda =4(b-a)$

So, $v=4n(b–a)$

Rest answers are theory based.