Question

72.
A wave equation is given by
y = 4 sint
5 9
sin -
X
at-
where, x is in cm and t is in seconds. The wavelength of
the wave is:
(a) 18 cm
(b) 9 cm
(c) 36 cm
(d) 6 cm​

Answer 1

Answer:

1.8cm/s

Explanation:

The given equation can be written as

y=4sin[π(t5−x9+16)]  …(i)

The standard wave equation can be written as

y=asin(2πTt−2πλ⋅x+ϕ)  …(ii)

Equating Eqs. (i) and (ii), we get

Amplitude, a = 4 cm

Frequency, f=1T=110Hz=0.1Hz

wavelength, λ=2×9=18cm

Velocity v=fλ=0.1×18=1.8cm/s