Question

Y=4sin (phi) (ax-bt)
jika cepat rambat gelombang 40 m/s dan a = 0,1 tentukan harga b dan persamaan gelombangnya !

Answer 1

Persamaan umum :
y = A sin 2π(ft-x/λ)

y = 4 sin π (ax-bt)
y = 4 sin 2π ((ax/2) - (bt/2)

A = 4
f = b/2
λ = 2/a

a= -yω²
0,1 = -4. 2πf
f = 0,1/-8π = -1/(80π)
b/2 = -1/(80π)
b = - 1/40π

v = λ.f
40 = 2/a . -(1/(80π))
a = -2 / 3200π = -1/1600π

persamaan umum
y = 4 sin π (ax-bt)
y = 4 sin π( (-1/(1600π) x)- ((-1/(80π) t)
y = 4 sin t/80 - x/1600