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Standing Wave

Why there is no (vt-x) in the standing wave equation?
Original post by Nxami
Why there is no (vt-x) in the standing wave equation?

Can you provide the details of the context? Which standing wave equations are you referring to?
Reply 2
y=Asin2π/wave length *(vt)
Original post by Nxami
y=Asin2π/wave length *(vt)


Not sure why are you writing the standing wave function partially.

Standing wave is superposition of two travelling waves that travel in the opposite direction.
Consider two identical waves that move in opposite directions. The first wave has a wave function of y1(x, t) = Asin(kx ωt) and the second wave has a wave function y2(x, t) = Asin(kx+ ωt) . The waves interfere and
form a resultant wave

y(x,t) = Asin(kx ωt) + Asin(kx+ ωt)

where k= 2π/λ and ω = 2π/T.

By using some trigonometric identities, we can simplify the above sum to

y(x,t) = [2A sin(kx)] cos(ωt)


The term in the square bracket describe the varying amplitude between two nodes.

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