Explanation:
The universal wave equation states that the velocity of a wave is the product of its wavelength and its frequency.
Mathematically speaking,
∣
∣
∣
∣
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
a
a
v
=
λ
f
a
a
∣
∣
−−−−−−−−−−−
where
−−−−−
:
v
=
velocity of wave (metres per second)
λ
=
wavelength (metres)
f
=
frequency (hertz or reciprocal seconds)
Step 1
Convert the given wavelength from centimetres into metres.
3.0
i
c
m
×
m
100
i
c
m
=
3.0
c
m
×
m
100
c
m
=
0.030
i
m
Step 2
Rearrange for frequency,
f
, in the universal wave equation.
v
=
λ
f
Becomes,
f
=
v
λ
Step 3
Substitute your known values to solve for the frequency of the pulse.
f
=
1500
i
m
s
0.030
i
m
f
=
50000
i
H
z
Rounding off the value to two significant figures,
f
=
∣
∣
∣
∣
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
a
a
5.0
×
10
4
i
H
z
a
a
∣
∣
−−−−−−−−−−−−−−−−
