Advertisements
Advertisements
प्रश्न
In a cathode ray tube state the purpose of covering cathode by thorium and carbon.
Advertisements
उत्तर
Purpose of covering cathode by thorium and carbon is to reduce its work function, decrease its melting point.
संबंधित प्रश्न
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?
Define bound electrons.
How is a cathode ray beam affected while passing through an electric field?
In a cathode ray tube state the purpose of the fluorescent screen.
Mention four properties of Becquerel rays.
The mean lives of a radioactive substance are 1620 and 405 years for β-emission and β-emission respectively. The time after which three fourth of a sample will decay if it is decaying both by β-emission and β-emission simultaneously will be ______ years.
(Take ln 2 = 0.693)
Assertion (A): Hydrogen atom consists of only one electron but its emission spectrum has may lines.
Reason (R): Only Lyman series is found in the absorption spectrum of hydrogen atom whereas in the emission spectrum, all the series are found.
What is the mass and charge of gamma rays?
