Advertisements
Advertisements
प्रश्न
The distance between the cathode (filament) and the target in an X-ray tube is 1.5 m. If the cutoff wavelength is 30 pm, find the electric field between the cathode and the target.
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
Advertisements
उत्तर
Given:
Distance between the filament and the target in the X-ray tube, d = 1.5 m
Cut off wavelength, `lambda = 30 "pm"`
Energy (E) is given by
`E = (hc)/lambda`
Here,
h = Planck's constant
c = Speed of light
`lambda` = Wavelength of light
Thus, we have
`E = (1242 "eV" - "nm")/(30 xx 10^-3)`
⇒ `E = (1242 xx 10^-9)/(30 xx 10^-12)`
⇒ `E = 41.4 xx 10^3 "eV"`
Now ,
`"Electric field" = V/d = (41.4 xx 10^3)/1.5`
= `27.6 xx 10^3 "V/m"`
= `27.6 "kV/m"`
APPEARS IN
संबंधित प्रश्न
A wave has wavelength 50 Å.
- Name the wave.
- State its speed in vacuum.
- State its one use.
Name the rays or waves of highest frequency .
Name the waves of wavelength nearly 0.1 nm.
Can X-rays be polarised?
The energy of a photon of a characteristic X-ray from a Coolidge tube comes from
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.)
Name the scientist who discovered Visible light
Name the scientist who discovered radio waves
Identify the part of the electromagnetic spectrum used in (i) radar and (ii) eye surgery. Write their frequency range.
Gamma rays and radio waves travel with the same velocity in free space. Distinguish between them in terms of their origin and the main application.
Give one use of electromagnetic radiations in Infrared radiation.
Answer briefly.
Why light waves travel in a vacuum whereas sound waves cannot?
Radio waves of constant amplitude can be generated with.
If λv, λx and λm Am represents the wavelength of visible light, x-ray and microwaves respectively, then ______.
The half-value thickness of an absorber is defined as the thickness that will reduce exponentially the intensity of a beam of particles by a factor of 2. The half-value thickness in (µm) for lead assuming X-ray beam of wavelength 20 pm, µ = 50 cm-1 for X-rays in lead at wavelength λ = 20 pm, is ______ µm.
Given below in the left column are different modes of communication using the kinds of waves given in the right column.
| A. | Optical Fibre Communication |
P. | Ultrasound |
| B. | Radar | Q. | Infrared Light |
| C. | Sonar | R. | Microwaves |
| D. | Mobile Phones | S. | Radio Waves |
From the options given below, find the most appropriate match between entries in the left and the right column.
Choose the correct option related to wavelengths (λ) of different parts of the electromagnetic spectrum.
Identify the part of the electromagnetic spectrum which:
- produces the heating effect.
- is absorbed by the ozone layer in the atmosphere.
- is used for studying crystal structure.
Write any one method of the production of each of the above radiations.
