Question

A tsunami originatig near the Alaska coast had a wavelength of 470 miles and traveled 2300 miles in 5.3 h. Determine the wave’s (a) speed in miles/hour and in m/s, (b) frequency and (c) period (in seconds and in minutes).

Answer 1

Answer:

a) 433.96 miles/hr

   193.98 m/s

b) 3899.3 Hz

c) 2.56 x 10^-4 $s^{-1}$

   0.015 $m^{-1}$

Explanation:

wavelength of the tsunami = 470 miles

Distance traveled = 2300 miles

time taken to travel this distance = 5.3 h

a) wave's speed = distance/time

==> 2300/5.3 = 433.96 miles/hr

1 miles/hr = 0.447 m/s

433.96 miles/hr = 433.96 x 0.447 = 193.98 m/s

b) frequency of a wave f = speed/wavelength

for wavelength, 470 miles = 470 x 1609.34 = 756389.8 m

frequency = 756389.8/193.98 = 3899.3 Hz

c) Period T = 1/frequency

T = 1/3899.3 = 2.56 x 10^-4 $s^{-1}$

60 sec = 1 min

Period T in sec = 2.56 x 10^-4 x 60 = 0.015 $m^{-1}$