Ask question

Ask question

All categories

3 years ago

11

An eagle flying at 35 m/s emits a cry whose frequency is 440 Hz. A blackbird is moving in the same direction as the eagle at 10

m/s. (Assume the speed of sound is 343 m/s.)
(a) What frequency does the blackbird hear (in Hz) as the eagle approaches the blackbird?
Hz
(b) What frequency does the blackbird hear (in Hz) after the eagle passes the blackbird?
Hz

1 answer:

Akimi4 [234]3 years ago

7 0

Answer:

a) $F=475.7Hz$

b) $F'=410.899Hz$

Explanation:

From the question we are told that:

Velocity of eagle $V_1=35m/s$

Frequency of eagle $F_1=440Hz$

Velocity of Black bird $V_2=10m/s$

Speed of sound $s=343m/s$

a)

Generally the equation for Frequency is mathematically given by

$F=f_0(\frac{v-v_2}{v-v_1})$

$F=440(\frac{343-10}{343-35})$

$F=475.7Hz$

b)

Generally the equation for Frequency is mathematically given by

$F'=f_0(\frac{v+v_2}{v+v_1})$

$F'=440(\frac{343+10}{343+35})$

$F'=410.899Hz$

You might be interested in

A rectangular loop with dimensions 4.20 cm by 9.50 cm carries current I. The current in the loop produces a magnetic field at th

rusak2 [61]

Answer:

1.63 A and in clockwise direction

Explanation:

The magnetic field due to the rectangular loop is :

$B=\frac{2 \mu_0 I}{\pi}\left(\frac{\sqrt{L^2+W^2}}{LW}\right)$

Given : W = 4.20 cm

$=4.20 \times 10^{-2} \ m$

L = 9.50 cm

$= 9.50 \times 10^{-2} \ m$

$B = 3.40 \times 10^{-5} \ T$

Rearranging the above equation, we get

$I=\frac{B \pi LW}{2 \mu_0\sqrt{L^2+W^2}}$

$I=\frac{(3.40 \times 10^{-5}) \pi(9.50 \times 10^{-2})(4.20 \times 10^{-2})}{2(4 \pi \times 10^{-7})\sqrt{(9.50 \times 10^{-2})^2+(4.20 \times 10^{-2})^2}}$

I = 1.63 A

So the magnitude of the current in the rectangular loop is 1.63 A.

And the direction of current is clockwise.

4 0

3 years ago

How might spontaneous generation be possible in a reducing environment? Question options: The reducing environment was created b

melomori [17]

Please help me with the unit assessment i have no idea any of the answers

7 0

3 years ago

An atom of element X has one more shell of electrons than an atom of beryllium, but it has one less valence electron than beryll

8090 [49]

Mg magnesium becuase one period down and one group to the side

7 0

3 years ago

Read 2 more answers

Use dimensional analysis to determine how the linear acceleration a in m/s2 of a particle traveling in a circle depends on some,

astraxan [27]

I have to say, i love this kind of problems.

So, we got the linear acceleration, as we all know, linear the acceleration its, in dimensional units:

$[a]=[\frac{distance}{time^2}]$ .

Now, we got the radius

$[r] = [distance]$

the angular frequency

$[\omega] = \frac{1}{s}$

and the mass

$[m]=[mass]$ .

Now, the acceleration doesn't have units of mass, so it can't depend on the mass of the particle.

The distance in the acceleration has exponent 1, and so does in the radius. As the radius its the only parameter that has units of distance, this means that the radius must appear with exponent 1. Lets write

$a \propto r$ .

The time in the acceleration has exponent -2 As the angular frequency its the only parameter that has units of time, this means that the angular frequency must appear, but, the angular frequency has an exponent of -1, this means it must be squared

$a \propto r \omega^2$ .

We are almost there. If this were any other problem, we would write:

$a = A r \omega^2$

where A its an dimensionless constant. Its common for this constants to appears if we need an conversion factor. If we wanted the acceleration in cm/s^2, for example. Luckily for us, the problem states that there is no dimensionless constant involved, so:

$a = r \omega^2$

5 0

3 years ago

This is a group of elements with few valence electrons that conducts heat and electricity.

k0ka [10]

Answer:

Metals

Explanation:

The group of elements with few valence electrons that conducts heat and electricity is known metals. Metals are good conductors of heat and electricity. The outer electrons in metals are loosely bound to the atom and are thus able to freely move around and conduct electricity and heat.

5 0

4 years ago