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प्रश्न
In a cathode ray tube state. How is it possible to increase the rate of emission of electrons.
उत्तर
(i) Decrease work function.
(ii) Coating the cathode with a layer of alkaline earth metallic oxides (or) hydrides.
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संबंधित प्रश्न
Under which conditions does the nucleus of an atom tend to radioactive?
Name the unit in which the work function of a metal is expressed.
A nucleus `""_11^24Na` emits a beta particle to change into Magnesium (Mg)
(i) Write the symbolic equation for the process.
(ii) What are numbers 24 and 11 called?
(iii) What is the general name of `""_12^24Mg `with respect to `""_11^24Na` ?
Give one example of isobars.
Draw a diagram of a simple atom showing the nucleus and electrons. In this atom:
(a) What type of charge will there be on the nucleus?
(b) What is the value of this charge?
Explain the use of radioactive in the field of medicine, agriculture and industry.
What is nucleus of an atom? Compare its size with that of the atom. Name its constitutents. How is the number of these constituents determined by the atomic number its atomic model.
Which of the following statements is/are correct?
- α particles are photons
- Penetrating power of γ radiation is very low
- Ionization power is maximum for α rays
- Penetrating power of γ radiation is very high
Heavy radioactive elements eventually turn into ______.
In U238 ore containing Uranium the ratio of U234 to Pb206 nuclei is 3. Assuming that all the lead present in the ore is final stable product of U238. Half life of U238 to be 4.5 × 109 years and the age of ore is ______ × 109 years. (in 109 years)
