1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Tema [17]
3 years ago
14

A bird is flying directly toward a stationary bird-watcher and emits a frequency of 1420 Hz. The bird-watcher, however, hears a

frequency of 1456 Hz. What is the speed of the bird, expressed as a percentage of the speed of sound
Physics
1 answer:
kogti [31]3 years ago
7 0

Answer:

2.47 %

Explanation:

We are given;

Frequency emitted by source(bird); f_s = 1420 Hz

Frequency heard by observer; f_o = 1456 Hz

From doppler shift frequency, we know that;

f_o = f_s [c/(c - c_s)]

Where c_s is speed of source which is the bird and c is speed of sound.

Thus;

Rearranging the equation, we have;

f_s/f_o = (c - c_s)/c

f_s/f_o = 1 - (c_s/c)

Plugging in the relevant values to get ;

1420/1456 = 1 - (c_s/c)

0.9753 = 1 - (c_s/c)

1 - 0.9753 = (c_s/c)

(c_s/c) = 0.0247

Since we want it expressed im percentage,

Thus, (c_s/c) % = 0.0247 x 100 = 2.47 %

You might be interested in
The earth orbits a start called the ____?
Aleks [24]

Answer:

the earth orbits a star called the sun

6 0
3 years ago
A river flows due south at 5 mi/h. A swimmer attempting to cross the river heads due east swimming at 3 mi/h relative to the wat
Dafna11 [192]

Answer:

<u>velocity of swimmer relative to ground = 3 i -5 j</u>

Explanation:

  • To cross a river the swimmer swims relative to river in perpendicular direction.

Velocity of river = -5 j (south)

Velocity of swimmer relative to river = 3 i(north)

So

<h2>Velocity of swimmer relative to ground = Velocity of swimmer relative to river + Velocity of river</h2>

Velocity of swimmer relative to ground = 3 i -5 j

So magnitude of total velocity is \sqrt{3^2+(-5)^2} =\sqrt{9+25} = \sqrt{34}

3 0
3 years ago
Name two effects of using coal as energy​
german

Answer:

Here is some useful background facts...

Explanation:

They include mercury, lead, sulfur dioxide, nitrogen oxides, particulates, and various other heavy metals. Health impacts can range from asthma and breathing difficulties, to brain damage, heart problems, cancer, neurological disorders, and premature death

7 0
3 years ago
Read 2 more answers
In a star nuclear fusion occurs in the
Anika [276]

Answer:

C. Core

Explanation:

8 0
2 years ago
How does the radius of a string affect centripetal force.
KiRa [710]

Answer:

because a raduis is half of 25% of a cicrle.

Explanation:

5 0
2 years ago
Other questions:
  • Megan was doing time trials on her bike around a 400m horizontal track. She took 32 seconds to travel 400m. What was her average
    7·2 answers
  • If a girl is standing in front of a smooth surface from which a sound is reflected, the girl may hear
    11·2 answers
  • 1. A roller coaster car rapidly picks up speed as it rolls down a slope. As it starts down the slope, its
    7·2 answers
  • Please answer this. Science 7th grade.
    5·1 answer
  • A small but bright light is at the bottom of a pool 2.2 m  deep. How wide is the circle of light that exits the surface of the
    14·1 answer
  • All the bulb in the series circuit are on or off together?
    12·1 answer
  • What is meant by lateral inversion​
    14·1 answer
  • In which example would the most transfer of energy take place from Mechanical energy to Thermal (heat) energy?
    15·1 answer
  • A Boeing 787 is initially moving down the runway at 6.0 m/s preparing for takeoff. The pilot pulls on the throttle so that the e
    13·1 answer
  • By what percent is the torque of a motor decreased if its permanent magnets lose 6.5 % of their strength
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!