Advertisements
Advertisements
Question
Answer briefly.
Can we produce a pure electric or magnetic wave in space? Why?
Solution
No.
In vacuum, an electric field cannot directly induce another electric field so a “pure” electric field wave cannot exist and same can be said for a “pure” magnetic wave.
APPEARS IN
RELATED QUESTIONS
If the earth did not have atmosphere, would its average surface temperature be higher or lower than what it is now? Explain.
Use the formula λm T= 0.29 cm K to obtain the characteristic temperature ranges for different parts of the electromagnetic spectrum. What do the numbers that you obtain tell you?
State an additional use of the X-rays waves
A wave has a wavelength of 10-3 nm. Name the wave.
What is the range of the wavelength of the following electromagnetic waves?
(A) Radio waves.
Name the radiations of wavelength just shorter than 4 × 10-7 m.
Give one use of microwaves.
Name the waves of wavelength nearly 0.1 nm.
Consider a photon of a continuous X-ray coming from a Coolidge tube. Its energy comes from
Moseley's Law for characteristic X-ray is √v = a(Z − b). Here,
One of the following wavelengths is absent and the rest are present in the X-rays coming from a Coolidge tube. Which one is the absent wavelength?
50% of the X-ray coming from a Coolidge tube is able to pass through a 0.1 mm thick aluminium foil. The potential difference between the target and the filament is increased. The thickness of the aluminium foil that will allow 50% of the X-ray to pass through will be
The potential difference applied to an X-ray tube is increased. As a result, in the emitted radiation,
(a) the intensity increases
(b) the minimum wavelength increases
(c) the intensity remains unchanged
(d) the minimum wavelength decreases.
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.
Consider a photon of continuous X-ray and a photon of characteristic X-ray of the same wavelength. Which of the following is/are different for the two photons?
The Kα X-rays of aluminium (Z = 13) and zinc (Z = 30) have wavelengths 887 pm and 146 pm respectively. Use Moseley's law √v = a(Z − b) to find the wavelengths of the Kα X-ray of iron (Z = 26).
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
The energy of a silver atom with a vacancy in K shell is 25.31 keV, in L shell is 3.56 keV and in M shell is 0.530 keV higher than the energy of the atom with no vacancy. Find the frequency of Kα, Kβ and Lα X-rays of silver.
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
Name the radiation of the electromagnetic spectrum which is used for the following:
Radar and Give the frequency range.
Name any two electromagnetic waves which have a frequency higher than that of violet light. State one use of each.
What is the wavelength of the wave whose frequency is 1012 Hz? Name the electromagnetic wave.
Answer briefly.
Why are microwaves used in radar?
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:-
Ozone layer above the earth's atmosphere will
Find the photon energy in units of ev for electromagnetic wave if waves length 40 m. Given h = 6.63 × 10–34 J.
In uranium (Z = 92) the K absorption edge is 0.107 Å and the Kα line is 0.126 Å, and the wavelength of the L absorption edge is ______.
Identify the electromagnetic wave whose wavelength range is from about 10-12 m to about 10-8 m. Write one use of this.
