Concepts Of Physics MCQ Edition [Volume 1]PhysicsWave Motion and Waves on a String
A wave travelling on a string stretched along the X -axis has an equation given by y = A , e^ - ( x a + t T )^2 . Identify the direction in which the wave is travelling.
Options
- APositive y -direction
- BNegative x -direction
- CNegative y -direction
- DPositive x -direction
Correct answer
B. Negative x -direction
Step-by-step solution
The given equation of the wave is y = A e^ - ( x a + t T )^2 . For a point on the wave with a constant phase, we have: x a + t T = constant Differentiating with respect to time t , we get: 1 a dx dt + 1 T = 0 dx dt = - a T Since the wave velocity dx dt is negative, the wave is travelling in the negative x -direction.