Answer:
Please selection one of the following
Answer: depth = 3.75 m
Explanation:
Taken the speed of the sound in sea to be V = 1500 m/s
The time between an echo sounder sending and receiving a pulse is 0.005 s. That is,
Total time T = 0.005
Formula for echo is:
V = 2X/T
Where X = distance covered
Substitute V and T into the formula
1500 = 2X/0.005
Cross multiply
7.5 = 2X
Make X the subject of formula
X = 7.5/2
X = 3.75 m
Therefore, the depth of the sea is 3.75 m
This is called vaporization.
hope this helps :)
Answer:
64.945 miles per hour
Explanation:
Since the frequency of sound heard is higher than actual frequency, the ambulance is moving towards you!
The frequency of sound waves as heard from a distance for a sound wave coming towards one at v₀ m/s and whose real frequency is f₀ is given by
+f = f₀/[1 - (v₀/v)]
+f = frequency of sound as heard from the distance away = 8.61 KHz
f₀ = real frequency of sound = 7.87 KHz
v₀ = velocity at which the sound source is moving towards the reference point = ?
v = velocity of sound waves = 343 m/s
8.61 = 7.87/(1 - (v₀/v))
1 - (v₀/343) = 0.9141
v₀/343 = 1 - 0.9141 = 0.0859
v₀ = 343 × 0.0859 = 29.48 m/s = 64.945 miles per hour
Thick lens will have shorter and consequently thin lens will have greater focal length. Because, For a thick lens, the optical path length of the light is more, than for a thin lens, thus, the bending of light will be more in case of a thicker lens. Consequently, it has a shorter focal length.
