Answer:
Speed at which the bat have to fly is 90.895 m/s away from the human (listener) in positive direction.
Explanation:
Given:
Frequency of the bat that is source here, 
= 25.3 kHz = 25.3 * 10^3 Hz
Frequency of the listener (human), 
= 20 kHz = 20*10^3 Hz
We have to identify how fast the bat have to fly in order for a person to hear these chirps .
Let the velocity of bat that is source is "Vs" and "Vs" = "Vbat".
Doppler effects formulae :
- When the source is receding (moving away)
- When the source is approaching
- Speed of sound in
the air (medium), 
Using the above formula and considering that the bat is moving away so that the human can listen the chirps also 
as listener is stationary.
⇒ ⇒ 
Re-arranging in terms of Vs.
⇒ 
⇒ 
⇒ 
⇒ 
m/s
The speed at which the bat have to fly is 90.895 m/s away from the human (listener) in positive direction.
Answer:
V= 4999.5 m/s
Explanation:
Given that
mass ,m= 605 gm
Length ,L= 0.75 m
width ,b= 0.01 m
height ,h= 0.03 m
frequency ,f= 3333 Hz
We know that
2 Length = Wavelength
λ= 2 x L
λ = 2 x 0.75 m
λ= 1.5 m
The speed V
V= f x λ
Now by putting the values
V= f x λ
V= 3333 x 1.5 m/s
V= 4999.5 m/s
Answer:
The relation is 
Explanation:
Generally the mathematically relation showing the relationship between the period(T), the constant (g) and the length(l) is
The answer is A: Core --> Mantle --> Crust.
Core: The earth's core is the center of the earth, which would ultimately be the deepest. The core is made up of alloy, which is a mixture of many medals, such as iron and nickel.
Mantle: The earth's mantle is the layer between the earths crust and core. Often made of silicate rocks.
Crust: The earth's crust is the outer-most of the three options. Usually made of up different types of rocks.
