Advertisements
Advertisements
प्रश्न
Identify the part of the electromagnetic spectrum which is suitable for radar system used in aircraft navigation.
Name the parts of the electromagnetic spectrum which is suitable for radar systems used in aircraft navigation.
Write in brief, how these waves can be produced.
Name the em waves which are suitable for radar systems used in aircraft navigation
Name an electromagnetic wave which is used in the radar system used in aircraft navigation
उत्तर
Microwaves or Radio waves are suitable for the radar system in aircraft navigation.
These rays are produced by special vacuum tubes, namely Klystrons, magnetrons and Gunn diodes.
APPEARS IN
संबंधित प्रश्न
Why are infra-red waves often called heat waves? Explain.
Can X-rays be used for photoelectric effect?
Is it possible that in a Coolidge tube characteristic Lα X-rays are emitted but not Kα X-rays?
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.
The Kβ X-ray of argon has a wavelength of 0.36 nm. The minimum energy needed to ionize an argon atom is 16 eV. Find the energy needed to knock out an electron from the K shell of an argon atom.
The electric current in an X-ray tube (from the target to the filament) operating at 40 kV is 10 mA. Assume that on an average, 1% of the total kinetic energy of the electron hitting hte target are converted into X-rays.
(a) What is the total power emitted as X-rays and (b) how much heat is produced in the target every second?
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.)
The electron beam in a colour TV is accelerated through 32 kV and then strikes the screen. What is the wavelength of the most energetic X-ray photon?
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
A free atom of iron emits Kα X-rays of energy 6.4 keV. Calculate the recoil kinetic energy of the atom. Mass of an iron atom = 9.3 × 10−26 kg.
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
The stopping potential in a photoelectric experiment is linearly related to the inverse of the wavelength (1/λ) of the light falling on the cathode. The potential difference applied across an X-ray tube is linearly related to the inverse of the cutoff wavelength (1/λ) of the X-ray emitted. Show that the slopes of the lines in the two cases are equal and find its value.
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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.
To which regions of the electromagnetic spectrum do the following wavelengths belong:
(a) 250 nm
(b) 1500 nm
Name the part of the electromagnetic spectrum which is:
Produced by bombarding a metal target with high electrons.
Identify the part of the electromagnetic spectrum used in
(i) radar and
(ii) eye surgery. Write their frequency range.
Give one use of electromagnetic radiation in Microwaves.
Answer briefly.
Does an ordinary electric lamp emit EM waves?
The magnetic field of a beam emerging from a filter facing a floodlight is given by B0 = 12 × 10–8 sin (1.20 × 107z – 3.60 × 1015t) T. What is the average intensity of the beam?
Assertion (A): Ultraviolet radiations is scattered more as compared to the microwave radiations.
Reason (R): Wavelength of ultraviolet radiation is more than the wavelength of microwave radiation.