question_answer

A travelling harmonic wave is represented by the equation where x and t are in meter and t is in seconds. Which of the following is a correct statement about the wave? [JEE Main 12-Jan-2019 Morning]

A) The wave is propagating along the positive x-axis with speed .

B) The wave is propagating along the positive x-axis with speed .

C) The wave is propagating along the negative x-axis with speed .

D) The wave is propagating along the negative x-axis with speed .

Correct Answer: C

Solution :

[c] The given wave is

Comparing with standard equation

Velocity

In the given equation x is positive. Therefore, the wave is travelling in the negative x-direction.