हिंदी

Answer briefly. Why light waves travel in a vacuum whereas sound waves cannot? - Physics

Advertisements
Advertisements

प्रश्न

Answer briefly.

Why light waves travel in a vacuum whereas sound waves cannot?

टिप्पणी लिखिए
Advertisements

उत्तर

Light waves are electromagnetic waves that can travel in a vacuum where sound waves travel due to the vibration of particles of the medium. Without any particles present (like in a vacuum) no vibrations can be produced. Hence, the sound wave cannot travel through the vacuum.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 13: Electromagnetic Waves and Communication System - Exercises [पृष्ठ २४०]

APPEARS IN

बालभारती Physics [English] Standard 11 Maharashtra State Board
अध्याय 13 Electromagnetic Waves and Communication System
Exercises | Q 2. (vii) | पृष्ठ २४०

वीडियो ट्यूटोरियलVIEW ALL [2]

संबंधित प्रश्न

What physical quantity is the same for X-rays of wavelength 10−10 m, red light of wavelength 6800 Å and radiowaves of wavelength 500 m?


Name the high energetic invisible electromagnetic waves which help in the study of the structure of crystals


State an additional use of the X-rays waves


The wavelengths for the light of red and blue colours are roughly 7.8 × `10^7` m and 4.8 × `10^7` m respectively.
(a) Which colour has the greater speed in vacuum?
(b) Which colour has the greater speed in glass?


Which radiation is used for satellite communication?


What is the range of the wavelength of the following electromagnetic waves?

(a)X-rays,


Give the range of wavelength of the electromagnetic waves visible to us.


State the approximate range of wavelength associated with infrared rays.


Give one use of microwaves.


Name the waves of wavelength nearly 0.1 nm.


Name two sources, each of infrared radiations and ultraviolet radiations.


Which part of electromagnetic spectrum is used in radar systems?


Can X-rays be used for photoelectric effect?


50% of the X-rays coming from a Coolidge tube are able to pass through a 0.1 mm thick aluminium foil. If the potential difference between the target and the filament is increased, the fraction of the X-rays passing through the same foil will be


X-ray incident on a material
(a) exerts a force on it
(b) transfers energy to it
(c) transfers momentum to it
(d) transfers impulse to it.


What potential difference should be applied across an X-ray tube to get X-ray of wavelength not less than 0.10 nm? What is the maximum energy of a photon of this X-ray in joule?

(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)


What is the cause of dispersion?

Name the radiation which can be detected by thermopile.


Arrange the following electromagnetic waves in increasing order of their frequencies (i.e. begin with the lowest frequency):
Visible light, y rays, X rays, microwaves, radio waves, infrared radiations, and ultraviolet radiation.


Name the radiation of the electromagnetic spectrum which is used for the following:

To photograph internal parts of the human body and Give the frequency range


What is the wavelength of the wave whose frequency is 1012 Hz? Name the electromagnetic wave.


Answer briefly.

Can we produce a pure electric or magnetic wave in space? Why?


What are the ultraviolet rays?


Answer briefly.

Name the most harmful radiation entering the Earth's atmosphere from outer space.


Answer briefly.

What is a carrier wave?


One requires 11eV of energy to dissociate a carbon monoxide molecule into carbon and oxygen atoms. The minimum frequency of the appropriate electromagnetic radiation to achieve the dissociation lies in ______.


Electromagnetic waves with wavelength

  1. λ1 is suitable for radar systems used in aircraft navigation.
  2. λ2 is used to kill germs in water purifiers.
  3. λ3 is used to improve visibility in runways during fog and mist conditions.

Identify and name the part of the electromagnetic spectrum to which these radiations belong. Also arrange these wavelengths in ascending order of their magnitude.


Electromagnetic waves of wavelengths λ1, λ2 and λ3 are used in a radar system, in water purifiers and in remote switches of TV, respectively.

  1. Identify the electromagnetic waves.
  2. Write one source for each of them.

Identify the electromagnetic wave whose wavelength range is from about 10-12 m to about 10-8 m. Write one use of this.


Choose the correct option related to wavelengths (λ) of different parts of the electromagnetic spectrum.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×