Advertisements
Advertisements
Question
Consider a photon of a continuous X-ray coming from a Coolidge tube. Its energy comes from
Options
the kinetic energy of the striking electron
the kinetic energy of the free electrons of the target
the kinetic energy of the ions of the target
an atomic transition in the target
Advertisements
Solution
the kinetic energy of the striking electron
In an X-ray tube, electrons are emitted by the filament when it is heated. An electric field generated by a DC battery between the filament and the target makes the electrons hit the target atoms with a very high speed. As a result, the electrons lose their kinetic energy to eject photons, which leads to a continuous emission of X-rays.
APPEARS IN
RELATED QUESTIONS
What role dose infra-red radiation play in physical therapy?
Identify the part of the electromagnetic spectrum which is suitable for radar system used in aircraft navigation.
To which part of electromagnetic spectrum does a wave of frequency 3 × 1013 Hz belong?
An X-ray beam can be deflected
The X-ray coming from a Coolidge tube has a cutoff wavelength of 80 pm. Find the kinetic energy of the electrons hitting the target.
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
The short-wavelength limit shifts by 26 pm when the operating voltage in an X-ray tube is increased to 1.5 times the original value. What was the original value of the operating voltage?
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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.)
| 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.
-
- Calculate the speed of the wave.
- Name the medium through which it is traveling.
State the name and the range of wavelength of the invisible electromagnetic waves beyond the red end of the visible spectrum.
State three properties of ultra-violet radiation similar to visible light.
What is the wavelength of the wave whose frequency is 1012 Hz? Name the electromagnetic wave.
Choose the correct option.
How does the frequency of a beam of ultraviolet light change when it travels from air into glass?
Write two uses of the following radiation.
Gamma rays
Name the electromagnetic radiation whose frequency is 10 Hz.
What is the wavelength range of electromagnetic radiation used in radio broadcast?
In an atom X, electrons absorb the energy from an external source. This energy “excites” the electrons from a lower-energy level to a higher-energy level around the nucleus of the atom. When electrons return to the ground state, they emit photons.
The figure below is the energy level diagram of atom X with three energy levels, E1 = 0.00eV, E2 = 1.78eV and E3 = 2.95eV. The ground state is considered 0 eV for reference. The transition of electrons takes place between levels E1 and E2.
- What wavelength of radiation is needed to excite the atom to energy level E2 from E1?
- Suppose the external source has a power of 100 W. What would be the rate of photon emission?
Which part of the electromagnetic spectrum is known as the visible spectrum?
What happens to wavelength as the frequency of electromagnetic radiation increases?
Which properties characterize X-rays?
