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
goldenfox [79]
3 years ago
8

The security alarm on a parked car goes off and produces a frequency of 960 Hz. The speed of sound is 343 m/s. As you drive towa

rd this parked car, pass it, and drive away, you observe the frequency to change by 75 Hz. At what speed are you driving
Physics
1 answer:
Greeley [361]3 years ago
7 0

Answer: 13.4\ m/s

Explanation:

Given

The frequency of the source is f_o=960\ Hz

Change in frequency is 75\ Hz

Speed of sound c=343\ m/s

Suppose v is the velocity of the observer

Doppler frequency is given by

f'=f_o\left(\dfrac{c\pm v_o}{c\pm v_s}\right)

Here, the source is at rest

While approaching source, frequency is

f_1=f_o\left(\dfrac{c+v}{c}\right)\quad \ldots(i)

While leaving, frequency is

f_2=f_o\left(\dfrac{c-v}{c}\right)\quad \ldots(ii)

The difference in the frequency is

\Rightarrow f_1-f_2=75\\\\\Rightarrow f_o\left(\dfrac{c+v}{c}\right)-f_o\left(\dfrac{c-v}{c}\right)=75\\\\\Rightarrow f_o\left(\dfrac{2v}{c}\right)=75\\\\\Rightarrow v=\dfrac{75\times 343}{2\times 960}\\\\\Rightarrow v=13.39\approx 13.4\ m/s

You might be interested in
a) Viewers of Star Trek hear of an antimatter drive on the Starship Enterprise. One possibility for such a futuristic energy sou
lina2011 [118]
Charge me and do I name for meters
3 0
3 years ago
In the realm of scientific inquiry, making an observation typically leads to ___.
musickatia [10]
A developing story hope it helped
5 0
4 years ago
Read 2 more answers
3. A 40.0-kg wagon is towed up a hill inclined at 18.5 with respect to the horizontal. The tow rope is parallel to the incline a
inn [45]
Force=tension-fg sin ∅
=140-mg sin 18.5
=140-124.35
=15.62N

a=f/m=15.62/40=0.39
now,
v²=u²+2as
=2×0.39×80
v²=62.4
v=7.8m/s
4 0
3 years ago
You can think of the work-kinetic energy theorem as the second theory of motion, parallel to Newton's laws in describing how out
kiruha [24]

Answer:

a) 4 289.8 J

b) 4 289.8 J

c) 6 620.1 N

d) 411 186.3 m/s^2

e) 6 620.1 N

Explanation:

Hi:

a)

The kinetic energy of the bullet is given by the following formula:

K = (1/2) m * v^2

With

    m = 16.1 g = 1.61 x 10^-2 kg

     v = 730 m/s

K = 4 289.8 J

b)

the work-kinetic energy theorem states that the work done on a system is the same as the differnce in kinetic energy of the same. Since the initial state of the bullet was at zero velocity (it was at rest)  Ki = 0, therefore:

W = ΔK = Kf - Ki  = 4 289.8 J

c)

The work done by a force is given by the line intergarl of the force along the trayectory of the system (in this case the bullet).

If we consider a constant force (and average net force) directed along the trayectory of the bullet, the work and the force will be realted by:

W = F * L

Where F is the net force and L is the length of the barrel, that is:

F = (4 289.8 J) / (64.8 cm) = (4 289.8 Nm) / (0.648 m) = 6620.1 N

d)

The acceleration can be found dividing the force by the mass:

a = F/m = (6620.1 N) /(16.1 g) = 411 186.3 m/s^2

e)

The force will have a magnitude equal to c) and direction along the barrel towards the exit

5 0
3 years ago
Sam and Ella are arguing at the baseball field. Sam says that if he throws a baseball with a greater speed, it will have a great
Elena L [17]
Don’t still need the answers or are u done and is it on edge
4 0
4 years ago
Read 2 more answers
Other questions:
  • Three people pull simultaneously on a stubborn donkey. Jack pulls eastward with a force of 64.7 N, Jill pulls with 61.5 N in the
    6·1 answer
  • The Electric Field 9.0m from a +25μC charge is 
    14·1 answer
  • How much work must be done on a 20-kg go-cart to increase its speed from 5 m/s to 10 m/s?
    15·2 answers
  • A bag of sugar weighs 1.50 lb on earth. what would it weigh in newtons on the moon, where the free-fall acceleration is one-sixt
    11·1 answer
  • How does acceleration differ from velocity
    14·2 answers
  • How do cells use food to make energy and maintain homeostasis?
    15·1 answer
  • A sailor drops a wrench from the top of a sailboat's vertical mast while the boat is moving rapidly and steadily straight forwar
    12·1 answer
  • two point charges having charge values of 9.2 E -6 C and 3.5 E -6 C, respectively, are separated by 3 E -2 m. What is the absolu
    7·1 answer
  • Why do stars appear so steady when viewed from the surface of moon or<br> by an astronaut in space?
    6·1 answer
  • A projectile is launched horizontally from a 20-m tall edifice with a vox of 25 m/s. How long will it take for the projectile to
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!