Advertisements
Advertisements
प्रश्न
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?
Advertisements
उत्तर
(a) In vacuum, both have the same speeds.
(b) In a glass, red light has greater speed.
संबंधित प्रश्न
Which radiation is used for satellite communication?
What is the range of the wavelength of the following electromagnetic waves?
(a) Visible.
Name the radiations of wavelength just longer than 8 × 10-7m.
Give one use of gamma rays.
Suppose a monochromatic X-ray beam of wavelength 100 pm is sent through a Young's double slit and the interference pattern is observed on a photographic plate placed 40 cm away from the slit. What should be the separation between the slits so that the successive maxima on the screen are separated by a distance of 0.1 mm?
Answer briefly.
Does an ordinary electric lamp emit EM waves?
For television broadcasting, the frequency employed is normally
The frequency of x-rays, y-rays and ultraviolet rays are respectively a, b and c. Then:-
Given below in the left column are different modes of communication using the kinds of waves given in the right column.
| A. | Optical Fibre Communication |
P. | Ultrasound |
| B. | Radar | Q. | Infrared Light |
| C. | Sonar | R. | Microwaves |
| D. | Mobile Phones | S. | Radio Waves |
From the options given below, find the most appropriate match between entries in the left and the right column.
Name one radiation having the wavelength longer than the wavelength of these radiations.
