Answer:
A. The waves in the water travel faster and at a higher frequency than they travel on land.
Explanation:
The main reason why human ears can hear dolphins' vocalizations while under the water but cannot hear them well on land is because water is denser than air and air particles travel faster in denser particles.
Denser particles also ensures that the frequency of the waves move faster which in turn produces a faster and louder result.
A kilogram is a unit of weight. So a kilogram of bricks would weigh the same as a kilogram of feathers despite if its in water or air since weight is determined by gravity in relation to mass and not what substance the object is in.
Complete question:
The exit nozzle in a jet engine receives air at 1200 K, 150 kPa with negligible kinetic energy. The exit pressure is 80 kPa, and the process is reversible and adiabatic. Use constant specific heat at 300 K to find the exit velocity.
Answer:
The exit velocity is 629.41 m/s
Explanation:
Given;
initial temperature, T₁ = 1200K
initial pressure, P₁ = 150 kPa
final pressure, P₂ = 80 kPa
specific heat at 300 K, Cp = 1004 J/kgK
k = 1.4
Calculate final temperature;
k = 1.4
Work done is given as;
inlet velocity is negligible;
Therefore, the exit velocity is 629.41 m/s
Answer:
Velocity = 0.0001389 m/s
Explanation:
Given that the
Distance covered = 1 metre
Time taken = 2 hours
Convert the hour to second
1 hour = 60 × 60 = 3600
2 hours = 2 × 3600 = 7200
What is the velocity of a worm moving 1 meter in 2 hours to the East?
Velocity can be referred as speed.
Velocity = distance/ time
Velocity = 1/7200
Velocity = 0.0001389 m/s
To solve this problem we will apply the concepts related to the Doppler Effect, defined as the change in apparent frequency of a wave produced by the relative movement of the source with respect to its observer. Mathematically it can be written as
Here,
= Frequency of the source
= Speed of the sound
= Speed of source
Now the velocity we have that
Then replacing our values,
Therefore the frequency of the observer is 1047.86Hz