Question

A wave represented by the equation : y = a cos (kx –wt) is superposed with another wave to form a stationary wave such that the point x = 0 is a node. The equation of the other wave is –

• A. a sin (kx + wt)
• B. – a cos (kx – wt)
• C. – a cos (kx + wt)
• D. – a sin (kx – wt)

Answer 1

Answer: (C)

– a cos (kx + wt)

Answer 2

At x = 0, node is formed that is reflection takes place from rigid end, So equation of reflected wave.

y = a cos (kx + wt + p)

= – a cos (kx + wt)