ask mattrab

1 Physics -- Wave Motion

Why are sound easier to hear at night than at day time?

Why are sound easier to hear at night than at day time?

1 Answers

8220 Views

Due to the refraction of sound, we can hear sounds easily at night than during clear days.

On a clear day, the lower layer of the atmosphere is hotter than the layers above. Since sound travels faster in a hotter medium, its speed is greater near the surface. As a result, the waves are bent away from the surface. Thus, the intensity of the sound waves diminishes and does not seem to travel a long distance. On a clear night, the lower layer of the atmosphere is colder than the air above. Now, the sound waves travel faster at the higher layers than at the lower layers. Thus, the waves are bent towards the earth's surface. The intensity of the sound increases and seems to travel a greater distance.

More questions on Wave Motion

Why are we able to hear short wave broadcast better than long wave broadcasts?

Because radio waves in the shortwave band can be reflected or refracted from the ionosphere.Therefore, short waves directed at an angle into the sky can be reflected back to Earth at great distances, beyond the horizon.

What are the differences between transverse and longitudinal waves?

The differences between transverse and longitudinal waves are as listed below:

Transverse waves
 Longitudinal waves
The particles of the medium vibrate in the direction perpendicular to

the direction of wave propagation.

 The particles of the medium vibrateparallel to the direction of wavepropagation.
Alternate crests and trough areformed.
 Alternate compression and rarefactionof the medium are formed.
These are formed in solids and overliquid surfaces.
 These are formed in...

What are the differences between progressive waves and stationary waves?

The differences between progressive waves and stationary waves are as listed below:

Progressive waves
 Stationary waves
The disturbance travels forward.

The disturbances are confined to aparticular region.
The amplitude of vibration ofeach particle is same.
 The amplitude is zero at nodes and goeson increasing to become maximum at antinodes.
Energy is transferred forwardalong the waves.
 No transfer of energy is in the medium.
No particles in the medium are atrest.

...

Here, I think the condition for formation of nodes and antinode are just swapped. The above equation of node predicts the position of node at the odd multiple of one fourth of wavelength but actual...

Why are we able to hear short wave broadcast better than long wave broadcasts?

Shortwave radio is used for broadcasting of voice and music, and long-distance communication to ships and aircraft, or to remote areas out of reach of wired communication or other radio services and that’s why it is more energetic than long waves. Shortwave radio is radio communication using the upper MF (medium frequency) and all of the HF (high frequency) portion of the radio spectrum, between 1,800–30,000 kHz. Shortwave radio received its name because the wavelengths in this band are...

What happens when you drop mercury in a glass vessel?

When Mercury is poured into the glass it forms many number of spherical droplets. This is due to the dominance of cohesive force on adhesive force. or we can say adhesive force is negligibly small.

Cohesion-it is the property of a substance to stick with its own kind, adhesion on the other hand is the property of a substance to stick with or gather with substance other than its own kind. And respectively the forces are cohesive and adhesive force.

A particle oscillates at frequency f. Then it's Kinetic energy oscillates at what frequency in terms of f?

A basic approach would be to use the definition of oscillation. One oscillation of Kinetic energy occurs when it reaches minimum(extreme position) from maximum( equilibrium position) and then to minimum. This process occurs twice in one oscillation of the particle, so the frequency at which the kinetic energy would oscillates is twice than that of the particle which is 2f.

A sound wave in a fluid medium is reflected at a barrier so that a standing wave is formed. The distance between nodes is 3.84 cm and the speed of propagation is 1520 m/s. Find the frequency.

The distance between nodes referred to in the problem means that that
λ/2=3.84cm, or
λ=0.077m. Therefore, the frequency is

f=v/λ=(1520m/s)/(0.077m)19740.25
Hz

A well with vertical sides and water at the bottom resonates at 7.20 Hz and at no lower frequency. The air in the well has a density of 1.21 kg/m3 and a bulk modulus of 1.41*105 Pa . How deep is th...

A tunnel leading straight through a hill greatly amplifies tones at 135 and 138 Hz. Find the shortest length the tunnel could have.

Two sources of sound are separated by a distance of 5.00 m. They both emit sound at the same amplitude and frequency, 300Hz, but they are 180 degree out of phase. At what point along the line conne...

A 30 cm violin string with linear mass density 0.625 g/m is placed near a loudspeaker that is fed by an audio oscillator of variable frequency. It is found that the string is set into oscillation o...

When a stone is thrown on the surface of water, a wave spreads out. From where does the energy come?  The kinetic energy of the stone imparts energy on the water molecules, on which it falls. So, t...

The energy carried by the water waves comes from kinetic energy of stone hitting the water surface.

Write four differences between standing wave and progressive wave.


Is an oscillation a wave? Give reason.

No, an oscillation is not a wave. The term wave implies the transfer of energy through successive vibrations of the particles of the medium. Hence, the oscillations of the body do not make up a wave.

Is an oscillation a wave? Give reason.

No, an oscillation is not a wave. The term wave implies the transfer of energy through successive vibrations of the particles of the medium. Hence, the oscillations of the body do not make up a wave.

Why explosions on other planets cannot be heard on earth?

Sound needs a material medium for its propagation from one place to another place. So sound cannot travel through vacuum. Since there is a vacuum between the planets and the earth, so the sound of explosions taking place on other planets cannot pass through this vacuum.

Which type of wave propaates in liquid? Explain . 

The type of wave that propagates in a liquid is called a mechanical wave. Mechanical waves are waves that require a medium to propagate, meaning they need a substance to travel through. In the case of liquid, such as water, mechanical waves can travel through it.


There are two primary types of mechanical waves that can propagate in a liquid: transverse waves and longitudinal waves.


1. Transverse Waves: In a transverse wave, the particles of the medium move perpendicular to the direction of wave...

Close Open App