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
dimulka [17.4K]
3 years ago
14

I NEED HELP!!!!!!!!!!!

Physics
1 answer:
nadezda [96]3 years ago
6 0

1. 168.1 Hz

To find the apparent frequency heard by the driver in the car, we can use the formula for the Doppler effect:

f'=(\frac{v\pm v_o}{v\pm v_s})f

where

f is the original sound of the horn

v is the speed of sound

v_o is the velocity of the observer (the driver and the car), which is positive if the observer is moving towards the source and negative if it is moving away

v_s is the velocity of the sound source (the train), which is positive if the source is moving away from the observer and negative otherwise

In this problem we have, according to the sign convention used:

v = 343 m/s\\f = 164 Hz\\v_o = -15 m/s\\v_s = -23 m/s

Substituting, we find:

f'=(\frac{343-15}{343-23})(164)=168.1 Hz

2.  2.96\cdot 10^8 m/s

The speed of light can be calculated as

v=\frac{d}{t}

where

d is the distance travelled

t is the time taken

In this problem:

d=2\cdot 3.85\cdot 10^8 =7.7\cdot 10^8 m is the total distance travelled by the laser beam (twice the distance between the Earth and the Moon)

t = 2.60 s is the time taken

Substituting in the formula,

v=\frac{7.7\cdot 10^8 m}{2.60 s}=2.96\cdot 10^8 m/s

You might be interested in
Does the mass of a parachute affect terminal velocity?
vovangra [49]

Answer:

The greater weight increases the terminal velocity by acting as an extra force against gravity and air resistance.

6 0
2 years ago
1. What was the Michelson-Morley experiment designed to do?2. When was the Michelson-Morley experiment done?3. What was the ethe
babymother [125]

Answer:

1) designed to measure the difference in speed of light in different directions , 1887

Explanation:

1) This experiment was designed to measure the difference in speed of light in different directions and therefore find the speed of the ether.

2) was made in 1887

3) At that time it was assumed that it was the medium in which light traveled and it is everywhere

4) the speed of the wave depends on the characteristics of the medium where it travels,

for the one in a string depends on the tension and density

for an electromagnetic wave of the permittivity and permeability of the vacuum

5) In this type of interferometer the beam is divided into two rays

6) In his interrupter, he had to accurately measure the displacement of the fringes in a telescope, for which he had to minimize vibrations, he had problems in the movement of one of the arms, changes in temperature

7) In Michelsom's second experiment, the apparatus could measure 0.01 fringes by increasing the length of the arms by 11 m

8) The new interferometer floated on a bed of mercury

9) Couldn't measure any difference in speed of light in different directions

10) Physics was forced to eliminate the concept of ETHER

11) One of the principles of relativities that the speed of light is constant in all inertial efficiency systems

12) Michelson in 1907

13) It seems that Einstein did not know the results of this experiment

6 0
3 years ago
I’ve already figured out A. I just need help with B and C.
Damm [24]

Answer:

595433.00

1456543.00

Explanation:

7 0
3 years ago
The diagram is being used to illustrate the second law of thermodynamics, where Qh represents a hot object and Qc represents a c
katrin [286]

Answer:

The answer is A. on edgen.

Explanation:

A. adding in the boxes an arrow that points from Qh to Qc

6 0
3 years ago
Read 2 more answers
An 85,000 kg stunt plane performs a loop-the-loop, flying in a 260-m-diameter vertical circle. at the point where the plane is f
konstantin123 [22]
A) When the plane is flying straight down, there are three forces acting on it:
- the centripetal force  F=m \frac{v^2}{r}, directed toward the center of the circle (so, horizontally)
- the weight of the plane: W=mg, downward, so vertically
- a third force, given by the propulsion of the plane, which is accelerating it towards the ground (because the problem says that the plane has an acceleration of a=12 m/s^2 towards the ground)

The radius of the circle is r= \frac{260 m}{2} = 130 m, so the centripetal force acting on the plane is
F_c=m \frac{v^2}{r} = \frac{(85000 kg)(55 m/s)^2}{130 m}=1.98 \cdot 10^6 N
On the vertical axis, we have two forces: the weight
W=mg=(85000 kg)(9.81 m/s^2)=8.34 \cdot 10^5 N
and the other force F given by the propulsion. Since we know that their sum should generate an acceleration equal to a=12 m/s^2, we can find the magnitude of this other force F by using Newton's second law:
F+mg=ma
F=m(a-g)=(85000kg)(12 m/s^2-9.81 m/s^2)=1.86 \cdot 10^5 N

So, the net force acting on the plane will be the resultant of the centripetal force (acting in the horizontal direction) and the two forces W and F (acting in the vertical direction):
R= \sqrt{(F_c^2+(W+F)^2}=
= \sqrt{(1.98\cdot 10^6N)^2+(8.34 \cdot 10^5N+1.86 \cdot 10^5 N)^2}  =2.23 \cdot 10^6 N

(b) The tangent of the angle with respect to the horizontal is the ratio between the sum of the forces in the vertical direction (taken with negative sign, since they are directed downward) and the forces acting in the horizontal direction, so:
\tan \theta =  \frac{-(W+F)}{F_c}= -0.5
And so, the angle is
\theta = \arctan (-0.5)=-26.8 ^{\circ}
 
7 0
3 years ago
Other questions:
  • The process of changing a property of a wave to transmit information is called .
    14·2 answers
  • A block of mass m slides with a speed vo on a frictionless surface and collides with another mass M which is initially at rest.
    11·1 answer
  • Bob is pushing a box across the floor at a constant speed of 1.2 m/s, applying a horizontal force whose magnitude is 75 N. Alice
    8·1 answer
  • How does the gravitational force exerted on earth by the sun with that exerted by the moon
    12·1 answer
  • The distance between the lenses in a compound microscope is 18 cm. The focal length of the objective is 1.5 cm. If the microscop
    7·1 answer
  • Which is the correct life sequence of a star?  
    11·2 answers
  • A 350 −Ω resistor and a 6.40 −μF capacitor are connected in parallel to an ac generator that supplies an rms voltage of 220 V at
    13·1 answer
  • What are the two main processes carried out by the excretory system?​
    6·1 answer
  • Methods to improve body composition by building muscle does not include which of the following behaviors? And why
    14·2 answers
  • Can someone please give me the answers to this? ... please ...
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!