Advertisements
Advertisements
प्रश्न
When 40 kV is applied across an X-ray tube, X-ray is obtained with a maximum frequency of 9.7 × 1018 Hz. Calculate the value of Planck constant from these data.
(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:-
Potential applied to the X-ray tube, V = 40 kV
Frequency of the X-ray, v = 9.7 × 1018 Hz
Wavelength (`lambda`) is given by
`lambda = (hc)/(eV)`
Here,
h = Planck's constant
c = Speed of light
`e = 1.6 xx 10^-19`
`therefore lambda = (hc)/(eV)`
`⇒ lambda/c = h/(eV)`
`⇒ 1/v = h/(eV) ..................(∵ v = c/lambda)`
`⇒ h = (eV)/v`
`⇒ h = (40 xx 10^3)/(9.7 xx 10^18) xx e`
`⇒ h = 4.12 xx 10^-15 "eVs"`
APPEARS IN
संबंधित प्रश्न
The wavelengths for the light of red and blue colours are roughly 7.8 × `10^7` m and 4.8 × `10^7` m respectively.
(a) Which colour has the greater speed in vacuum?
(b) Which colour has the greater speed in glass?
Give the range of wavelength of the electromagnetic waves visible to us.
Is it possible that in a Coolidge tube characteristic Lα X-rays are emitted but not Kα X-rays?
Can Lα X-ray of one material have shorter wavelength than Kα X-ray of another?
X-ray from a Coolidge tube is incident on a thin aluminium foil. The intensity of the X-ray transmitted by the foil is found to be I0. The heating current is increased to increase the temperature of the filament. The intensity of the X-ray transmitted by the foil will be
(a) zero
(b) < I0
(c) I0
(d) > I0
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?
Continuous X-rays are made to strike a tissue paper soaked with polluted water. The incoming X-rays excite the atoms of the sample by knocking out the electrons from the inner shells. Characteristic X-rays are analysed and the intensity is plotted against the wavelength. Assuming that only Kα intensities are detected, list the elements present in the sample from the plot. Use Moseley's equation v − (25 × 1014Hz)(Z − 1)2.
(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 Microwaves
| Gamma rays | D | C | Visible light | B | A |
The above table shows different parts of the electromagnetic spectrum.
(a) Identify the parts of the spectrum marked as A, B, C and D.
(b) Which of the radiations A or B has the higher frequency?
(c) State two properties which are common to all parts of the electromagnetic spectrum.
(d) Name one source of each of the radiation of electromagnetic spectrum.
(e) Name one detector for each of the radiation.
(f) Name one use of each of the radiation.
Identify the part of the electromagnetic spectrum used in
(i) radar and
(ii) eye surgery. Write their frequency range.
Choose the correct option.
Earth’s atmosphere is richest in
The fundamental frequency of an open organ pipe is 300 Hz. The first overtone of this pipe has same frequency as first overtone of a closed organ pipe. If speed of sound is 330 m/s, then the length of closed organ pipe is:
Following QN ∴ 14, the radiation force on the roof will be
A radio can tune to any station in the 7.5 mHz to 12 MHz band. What is corresponding wave length band.
One requires 11eV of energy to dissociate a carbon monoxide molecule into carbon and oxygen atoms. The minimum frequency of the appropriate electromagnetic radiation to achieve the dissociation lies in ______.
Write two uses of the following radiation.
Gamma rays
Which one of the following electromagnetic radiation has the least wavelength?
Name the electromagnetic radiation that has been used in obtaining the image below.

