PLEASE HELP!!!!

A Explain why the sound produced by the horn of an approaching car

aleksklad [387]

When a car approaches you, the sound waves that reach you have a shorter wavelength and a higher frequency. You hear a sound with a higher pitch. When the car moves away from you, the sound waves that reach you have a longer wavelength and lower frequency.

?? ⬇️

An approaching source moves closer during period of the sound wave so the effective wavelength is shortened, giving a higher pitch since the velocity of the wave is unchanged. Similarly the pitch of a receding sound source will be lowered.

The Doppler effect is an effect observed in light and sound waves as they move toward or away from an observer. One simple example of the Doppler effect is the sound of an automobile horn. Picture a person standing on a street corner. A car approaches, blowing its horn.

Comparing two waves of the same wavelength, a higher frequency is associated with faster movement. Comparing two waves of different wavelengths, a higher frequency doesn't always indicate faster movement, although it can. Waves of different wavelengths can have the same frequency.

The pitch of a sound is our ear's response to the frequency of sound. Whereas loudness depends on the energy of the wave. ... The pitch of a sound depends on the frequency while loudness of a sound depends on the amplitude of sound waves.

5 0

2 years ago

Light waves have some similarities with water and sound waves, but they are not exactly the same. Describe all the differences y

makkiz [27]

Answer:

<h2>All the waves are pertubations that propagate (transport) energy.</h2><h2></h2>

Nevertheless, they have some differences:

1. Light waves are electromagnetic waves, while sound and water waves are mechanical waves, this is the first and principal difference.

2. Electromagnetic waves can propagate in vacuum (they do not need a medium or material), but mechanical waves obligatory need a material to propagate

3. Light waves are always transversal waves, this means the oscillatory movement is in a direction that is perpendicular to the propagation; but mechanical waves may be both: longitudinal waves (the oscillation occurs in the same direction as the propagation) or transversal waves.

4. Electromagnetic waves propagates at a constant velocity (Light velocity) while the velocity of mechanical waves will depend on the type of wave and the density of the medium or material.

5. Mechanical waves are characterized by the regular variation of a single magnitude, while electromagnetic waves are characterized by the variation of two magnitudes: the electric field and the magnetic field

6. Water waves are 2-dimensional waves, while the light and the sound are tridimensional spherical waves

7. Light waves transports energy in the form of radiation, while mechanical waves transport energy with material

3 0

2 years ago

A 4.0 cm × 4.2 cm rectangle lies in the xy-plane. You may want to review (Pages 664 - 668) . Part A What is the electric flux th

padilas [110]

Answer:

(A). The flux is 0.336 N.m²/C

(B). The flux is zero.

Explanation:

Given that,

Length = 4.2 cm

Width = 4.0 cm

Electric field $E=(150 i-200 k)\ N/C$

Area vector is perpendicular to xy plane

(A). We need to calculate the flux

Using formula of flux

$\phi=E\cdot A$

Where, E = electric field

A = area

Put the value into the formula

$\phi=(150 i-200 k)\times(4.2\times10^{-2}\times4.0\times10^{-2})k$

$\phi=-200\times4.2\times10^{-2}\times4.0\times10^{-2}$

$\phi=-0.336\ N.m^2/C$

(B). Given electric field

$E=(150i-200j)\ N/C$

We need to calculate the flux

Using formula of flux

$\phi=E\cdot A$

Put the value into the formula

$\phi=(150 i-200 j)\times(4.2\times10^{-2}\times4.0\times10^{-2})k$

Here, The component of k is not given

So, the flux is

$\phi=0$

Hence, (A). The flux is -0.336 N.m²/C

(B). The flux is zero.

7 0

3 years ago

Read 2 more answers

What is the speed of a wave frequency of 300hz and a wavelength of 25M

tia_tia [17]

Answer:

7500 m/s

Explanation:

We can use the equation velocity of a wave equals wavelength times frequency. Therefore, v = wavelength*f = (25 m)(300 Hz) = m/s7,500

8 0

3 years ago

A spherical shell has inner radius Rin and outer radius Rout. The shell contains total charge Q, uniformly distributed. The inte

Tju [1.3M]

Answer:

E = Q / 4 π ε₀ (r-R_int) / (R_put³ -R_int³)

Explanation:

For this exercise we can use Gauss's law

Ф = ∫ E. dA = $q_{int}$ / ε₀

Where q is the charge inside the surface.

In this case the surface must be a sphere, the electric field lines and the radius of the sphere are parallel, so the scalar product is reduced to the algebraic product

∫ E dA = q_{int}/ ε₀

The area of a sphere is

A = 4π r²

- The electric field for a distance r < R_int

The charge inside is zero, so the electric field

E = 0 r <R_in t

- The field for a radio inside the shell

Let's use the concept of density

ρ = Q / V

q = ρ (4/3 π r³)

dq = ρ 4π r² dr

We substitute in the Gaussian equation

E ∫ dA = ρ 4π r² dr / ε₀

E 4π r² = ρ 4π/ε₀ r³ / 3

E = ρ / 3ε₀ r

We evaluate between the lower limit r = R_int, E = 0 and the upper limit r = r, E = E

E- 0 = ρ / 3ε₀ (r –R_int)

Density is

ρ = q / 4/3 π (R_out³ - R_int³)

Where R <r

E = Q / 4 π ε₀ (r-R_int) / (R_put³ -R_int³)

5 0

3 years ago