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प्रश्न
The X-ray beam emerging from an X-ray tube
पर्याय
is monochromatic
has all wavelengths smaller than a certain maximum wavelength
has all wavelengths greater than a certain minimum wavelength
has all wavelengths lying between a minimum and a maximum wavelength
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उत्तर
has all wavelengths greater than a certain minimum wavelength
The X-ray beam emerging from an X-ray tube consists of wavelengths greater than a certain minimum wavelength called cutoff wavelength.
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संबंधित प्रश्न
Given below are some famous numbers associated with electromagnetic radiations in different contexts in physics. State the part of the electromagnetic spectrum to which each belongs.
(a) 21 cm (wavelength emitted by atomic hydrogen in interstellar space).
(b) 1057 MHz (frequency of radiation arising from two close energy levels in hydrogen; known as Lamb shift).
(c) 2.7 K [temperature associated with the isotropic radiation filling all space-thought to be a relic of the ‘big-bang’ origin of the universe].
(d) 5890 Å - 5896 Å [double lines of sodium]
(e) 14.4 keV [energy of a particular transition in 57Fe nucleus associated with a famous high resolution spectroscopic method (Mössbauer spectroscopy)].
Why are infra-red waves often called heat waves? Explain.
State the approximate range of wavelength associated with infrared rays.
Give one use of ultraviolet radiation.
Which part of electromagnetic spectrum is used in radar systems?
Can X-rays be polarised?
Characteristic X-rays may be used to identify the element from which they are being emitted. Can continuous X-rays be used for this purpose?
A certain element emits Kα X-ray of energy 3.69 keV. Use the data from the previous problem to identify the element.
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
State the name and the range of wavelength of the invisible electromagnetic waves beyond the red end of the visible spectrum.
Name three radiations and their wavelength range which are invisible and beyond the violet end of the visible spectrum.
State two uses of infrared radiations.
Answer briefly.
Why light waves travel in a vacuum whereas sound waves cannot?
A car is moving towards a high cliff. The car driver sounds a horn of frequency f. The reflected sound heard by the driver has a frequency 2f. If v be the velocity of sound, then the velocity of the car, in the same velocity units, will be:
A radio can tune to any station in the 7.5 mHz to 12 MHz band. What is corresponding wave length band.
Why does microwave oven heats up a food item containing water molecules most efficiently?
Electromagnetic waves with wavelength
- λ1 is used in satellite communication.
- λ2 is used to kill germs in water purifies.
- λ3 is used to detect leakage of oil in underground pipelines.
- λ4 is used to improve visibility in runways during fog and mist conditions.
- Identify and name the part of electromagnetic spectrum to which these radiations belong.
- Arrange these wavelengths in ascending order of their magnitude.
- Write one more application of each.
Which set lists uses of microwaves?
How does the frequency of infrared radiation compare with that of microwaves?
Which part of the electromagnetic spectrum can the human eye detect?
