An ultrasound signal of frequency 50 kHz is sent vertically into sea water. The signal gets reflected from the ocean bed and returns to the surface 0.80 s after it was emitted. The speed of sound in sea water is `1500ms^-1`. a) Find the depth of the sea. b) What is the wavelength of this signal in water.

Explanation

a. Let the depth of the sea be d. the total distance travelled by the sigN/Al is 2d. By the question,
`2d=(1500ms^-1)(0.8s)=1200m`
or `d=600m`
b. using the equation `v=vlamda`
`lamda=v/v=(1500ms^1)/(50xx10^3s^-1)=3.0cm`