NUCLEAR PHYSICS
_____ discovered positive rays
Positive rays were named as protons by___
In 1911, the British scientist, Ernest Rutherfordexplained that the mass of an atom is concentrated in its central part called ____
____ and her husband ____detected radioactivity in ‘Pitchblende’, a tiny black substance.
The elements whose atomic number is more than ___ undergo spontaneous radioactivity. Eg: uranium, radium, etc.
There are only two elements, which have been identified as radioactive substances with atomic number less than 82. They are ____
Technetium (Tc) atomic number is___
Promethium (Pm) atomic number is___
There have been ___ radioactive substances discovered so far.
The phenomenon by which even light elements are made radioactive, by artificial or induced methods, is called____
A nuclear reaction in which an unstable parent nucleus emits an alpha particle and forms a stable daughter nucleus, is called____.
A nuclear reaction, in which an unstable parent nucleus emits a beta particle and forms a stable daughter nucleus, is called____
The process of breaking (splitting) up of a heavier nucleus into two smaller nuclei with the release of a large amount of energy and a few neutrons is called___
A fissionable material is a radioactive element, which undergoes fission in a sustained manner when it absorbs a neutron.
It is also termed as____
There are some radioactive elements, which can be converted into fissionable material. They are called as_____
A ____ is a self�propagating process in which the number of neutrons goes on multiplying rapidly almost in a geometrical progression
The minimum mass of a fissile material necessary to sustain the chain reaction is called ______
The process in which two lighter nuclei combine to form a heavier nucleus is termed ___as ___
The stars like our Sun emit a large amount of energy in the form of light and heat. This energy is termed as the____
The energy released in a hydrogen bomb (or fusion bomb) is much higher than that released in an ____
____ are used as tracers to diagnose the nature of circulatory disorders of blood, defects of bone metabolism, to locate tumors, etc
____ is used to cure goiter.
Radio cobalt (Co60) and radio-gold (Au198) are used in the treatment of___ skin
____ are used to sterilize the surgical devices as they can kill the germs and microbes.
In industries, ___are used as tracers to detect any manufacturing defects such as cracks and leaks.
Using the technique of ____, the age of the Earth, fossils, old paintings and monuments can be determined.
A ____’ is a device in which the nuclear fission reaction takes place in a self-sustained and controlled manner to produce electricity
___ are used to control the number of neutrons in order to have sustained chain reaction.