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प्रश्न
When a Coolidge tube is operated for some time it becomes hot. Where does the heat come from?
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उत्तर
A Coolidge tube apparatus consists of a filament and a target. The filament is heated to produce electrons that are accelerated by applying an electric field between the filament and the target. When these accelerated electrons enter the target, they collide with the target atoms. In the process, the electrons lose their kinetic energy. A part of this kinetic energy is utilised for emitting X-rays and the remaining energy is absorbed by the target. Inside the target, the kinetic energy of the electrons is converted into heat energy. This raises the temperature of the target and hence, it heats the Coolidge tube.
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संबंधित प्रश्न
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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.
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How are X-rays produced?
The X-ray beam emerging from an X-ray tube
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
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(Use Planck constant h = 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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(a) 250 nm
(b) 1500 nm
Give one use of electromagnetic radiation in Ultraviolet radiation.
Name the radiations used for the detection of fracture in bones.
Choose the correct option.
The EM wave emitted by the Sun and responsible for heating the Earth’s atmosphere due to greenhouse effect is
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- is absorbed by the ozone layer in the atmosphere.
- is used for studying crystal structure.
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| Gamma ray | X - ray | UV rays | Visible rays | Infrared | A | Radio waves |
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- What wavelength of radiation is needed to excite the atom to energy level E2 from E1?
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