68.
(a) Using v = f λ, we obtain
f =
240 m/s
3.2 m
= 75 Hz .
(b) Since frequency is the reciprocal of the period, we find
T =
1
f
=
1
75 Hz
= 0.0133 s
≈ 13 ms .
68.
(a) Using v = f λ, we obtain
f =
240 m/s
3.2 m
= 75 Hz .
(b) Since frequency is the reciprocal of the period, we find
T =
1
f
=
1
75 Hz
= 0.0133 s
≈ 13 ms .