Advertisements
Advertisements
प्रश्न
What are cathode rays? Why are they called ‘cathode rays’? Name a material which exhibits fluorescence when cathode rays fall on it.
उत्तर
Cathode rays are the stream of negatively charged particles called electrons. They are called cathode rays because they are given out from cathode in a discharge tube operating at about 10,000 V when the pressure inside the tube is about 0.01 mm of Hg. Zinc Sulphide exhibits fluorescence when cathode rays fall on it.
APPEARS IN
संबंधित प्रश्न
Under which conditions does the nucleus of an atom tend to radioactive?
Why is a cathode ray tube evacuated to a low pressure?
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` ?
Name two radioactive substances.
During the emission of a beta particle, the ______ number remains same.
Define free electrons.
How is a cathode ray beam affected while passing through an electric field?
In a cathode ray tube state the purpose of covering cathode by thorium and carbon.
Are all the radiations viz. α, β and γ emitted in a single radioactive decay?
State one use of radio-isotopes.
