Science Question. Physics. Please include units and workings if possible.?

If you can express this as y = A*sin[k(x - ct)], then the "c" is the wave speed. So let's try that...

y = 0.17*sin(9.1*pi*t + 0.85*pi*x)

= 0.17*sin[(0.85 pi)*(x + 10.706t)].

So the speed of the wave is 10.706 m/s in the negative direction.

Compare the given wave equation with standard wave equation:

y = A sin (kx - ωt) and get,

k = 8.85 π rad/m

ω = 9.1 π rad/s

v = ω/k = (9.1/8.85) m/s = 10.7 m/s

Hint. You are much more likely to get answers (especially from people who have answered your previous questions) if you choose Best Answer sometimes.

Some background:

A general equation of a plane wave moving in the +x direction is:

y = Asin(kx - ωt)

For a wave moving in the =-x direction we can use:

y = Asin(kx + ωt) (equation 1)

The constant, k, in front of x is called the wavenumber: k = 2π/λ

The constant. ω, in front of t is called the angular frequency: ω = 2πf

For a wave, v = λf = (2π/k)(ω/2π) = ω/k

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You are given y = 0.17sin(9.1πt + 0.85πx). By matching coefficients of x and t with equation 1 you see:

k = 0.85π

ω = 9.1π

v = ω/k = 9.1π/(0.85π) = 10.7m/s