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प्रश्न
An electromagnetic wave has a frequency of 500 MHz and a wavelength of 60 cm.name the medium through which it is travelling
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उत्तर
Electromagnetic wave is travelling through air.
संबंधित प्रश्न
What role dose infra-red radiation play in physical therapy?
Give a reason for the following:
Long-distance radio broadcasts use short-wave bands. Why?
Two waves A and B have wavelength 0.01 Å and 9000 Å respectively.
- Name the two waves.
- Compare the speeds of these waves when they travel in vacuum.
Can X-rays be used for photoelectric effect?
If the operating potential in an X-ray tube is increased by 1%, by what percentage does the cutoff wavelength decrease?
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
State three properties of ultra-violet radiation similar to visible light.
Answer briefly.
Give two uses of radio waves.
A radio can tune to any station in the 7.5 mHz to 12 MHz band. What is corresponding wave length band.
The ratio of contributions made by the electric field and magnetic field components to the intensity of an EM wave is ______.
In an atom X, electrons absorb the energy from an external source. This energy “excites” the electrons from a lower-energy level to a higher-energy level around the nucleus of the atom. When electrons return to the ground state, they emit photons.
The figure below is the energy level diagram of atom X with three energy levels, E1 = 0.00eV, E2 = 1.78eV and E3 = 2.95eV. The ground state is considered 0 eV for reference. The transition of electrons takes place between levels E1 and E2.
- What wavelength of radiation is needed to excite the atom to energy level E2 from E1?
- Suppose the external source has a power of 100 W. What would be the rate of photon emission?
