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
Semenov [28]
3 years ago
7

A stationary motion detector sends out a sound wave of frequency f = 3.3-hz towards an approaching car. the wave is reflected of

f the car and the reflected wave is picked up by the motion detector. when the reflected wave is superimposed on the original wave, it is found that the sum produces a beat frequency fbeat = 0.070-hz. find the speed of the car. you may assume the speed of sound in air to be 340-ms-1
Physics
1 answer:
Eva8 [605]3 years ago
3 0
Thank you for posting your question here. Below is the solution:

fbeat = (f' - f) / 2 
<span>then </span>
<span>f' = 2 fbeat + f = 4.126 Hz </span>
<span>also </span>
<span>f' = f vs / (vs - v) </span>
<span>then </span>
<span>v = (f' - f) vs / f' </span>
<span>v = (4.126 - 4)*340 / 4.126 = 10.383 m/s</span>
You might be interested in
Convert 1nanosecond in to its SI init
SOVA2 [1]

<em>Convert 1nanosecond in to its SI init</em>

<em>In SI units, nano is 1000th part of micro which in turn is 1000th part of mini which in turn is 1000th part of main unit. Now, when you affix nano to any unit, here in case, second, it means that you are referring to 1000th part of 1000th part of 1000th part of second or in short, 1000000000th(10^9) part of a second.</em>

<em>In SI units, nano is 1000th part of micro which in turn is 1000th part of mini which in turn is 1000th part of main unit. Now, when you affix nano to any unit, here in case, second, it means that you are referring to 1000th part of 1000th part of 1000th part of second or in short, 1000000000th(10^9) part of a second.So to convert nanosecond into second, just multiply the nanosecond with 0.000000001 or (10^-9)</em>

8 0
3 years ago
A bottle lying on the windowsill falls off and takes 4.95 seconds to reach the ground. The distance from the windowsill to the g
mr Goodwill [35]

The distance an object falls from rest through gravity is

                         D  =  (1/2) (g) (t²)

            Distance  =  (1/2 acceleration of gravity) x (square of the falling time)

We want to see how the time will be affected
if  ' D ' doesn't change but ' g ' does.
So I'm going to start by rearranging the equation
to solve for ' t '.

                                                      D  =  (1/2) (g) (t²)

Multiply each side by  2 :         2 D  =            g    t² 

Divide each side by ' g ' :      2 D/g =                  t²

Square root each side:        t = √ (2D/g)


Looking at the equation now, we can see what happens
to ' t ' when only ' g ' changes: 

-- ' g ' is in the denominator; so bigger 'g' ==> shorter 't'
                                             and smaller 'g' ==> longer 't' .

-- They don't change by the same factor, because  1/g  is inside
the square root.  So 't' changes the same amount as  √1/g  does.

Gravity on the surface of the moon is roughly  1/6  the value
of gravity on the surface of the Earth.

So we expect ' t ' to increase by  √6  =  2.45 times.

It would take the same bottle  (2.45 x 4.95) = 12.12 seconds
to roll off the same window sill and fall 120 meters down to the
surface of the Moon.
4 0
4 years ago
Read 2 more answers
What causes an air conditioned to turn on
Flura [38]

Answer:

The amount of heat or moisture in the air

Explanation:

Or a switch

7 0
4 years ago
An old theory about the creation of the universe has been replaced by a new theory. Which of these statements is correct about t
frez [133]

Answer:

A because it was rejected as it cannot become a law it was totally wrong as compared to today's information about out universe that how big bang theory was there.... So it is right the option A

8 0
1 year ago
Imagine holding a basketball in both hands, throwing it straight up as high as you can, and then catching it when it falls. At w
valentina_108 [34]

Answer:before throwing and after catching the ball

Explanation:

When basketball is in the hand of player net force on it zero as holding force is canceled by gravity Force. During its entire motion gravitational force is acting on the ball which is acting downward. Even at highest point gravity is constantly acting downwards.

After catching the ball net force on it zero as holding force is canceled by gravity force and ball is continue to be in stationary motion.          

6 0
3 years ago
Other questions:
  • which of the following do you calculate when you divide the total distance traveled by the total travel time
    13·2 answers
  • 1. What is the velocity if the displacement is 50 m and the time interval is 10 s?
    9·1 answer
  • According to Newton’s Third Law of Motion, how are action and reaction forces related. Provide a full explanation with an exampl
    13·1 answer
  • The impulse of a constant force is equal to
    14·1 answer
  • Identify the reaction type for each generic chemical equation. A + B → AB: AB → A + B: Hydrocarbon + O2 → CO2 + H2O: AB + CD →
    13·2 answers
  • What is the relationship between kinetic and potential energy of a falling object
    7·1 answer
  • A constellation’s changing position in the sky, at the same time of the evening, over a period of several weeks is evidence that
    15·1 answer
  • Un neumático sin cámara, soporta una presión de 1.5 atm cuando la temperatura ambiente es de 300°K. ¿Qué presión llegará a sopor
    10·1 answer
  • Two people stand facing each other at a roller skating rink then push off each other. a). What is the momentum of the system bef
    10·1 answer
  • ——-<br><br><br><br> need an answer asap!!
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!