Advertisements
Advertisements
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?
Advertisements
उत्तर
The speed of light (3 × 108 m/s) in a vacuum is the same for all wavelengths. It is independent of the wavelength in the vacuum.
संबंधित प्रश्न
What role dose infra-red radiation play in physical therapy?
If the earth did not have an atmosphere, would its average surface temperature be higher or lower than what it is now?
What is the range of the wavelength of the following electromagnetic waves?
(a) Infrared.
Name the region beyond the red end of the spectrum.
Name the region beyond the violet end of the spectrum called.
Name the waves produced by the changes in the nucleus of an atom.
Moseley's Law for characteristic X-ray is √v = a(Z − b). Here,
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.
Heat at the rate of 200 W is produced in an X-ray tube operating at 20 kV. Find the current in the circuit. Assume that only a small fraction of the kinetic energy of electrons is converted into X-rays.
Name two sources of ultraviolet radiation.
Choose the correct option.
The EM wave emitted by the Sun and responsible for heating the Earth’s atmosphere due to greenhouse effect is
Answer briefly.
Why are microwaves used in radar?
Answer briefly.
Does an ordinary electric lamp emit EM waves?
Answer briefly.
What are radio waves?
Solve the numerical problem.
Calculate the wavelength in nm of an X-ray wave of frequency 2.0 × 1018 Hz.
Name the e.m. waves which are suitable for radar systems used in aircraft navigation. Write the range of frequency of these waves.
X-rays, gamma rays and microwaves travelling in a vacuum have ______.
Name one radiation having the wavelength longer than the wavelength of these radiations.
Name the electromagnetic radiation that has been used in obtaining the image below.

