If you would like to become a nuclear physicist, what you would like to know about the nucleus first?

A. structure of the nucleus

Every atom consists of a dense positive central core of mass, known as nucleus. Its size is much smaller compared to the size of the atom, nut nonetheless it contains almost all of the mass of the atom.

The nucleus is made of only neutrons and protons. — These are collectively known as nucleons. 

Nucleons are not the smallest constituents of matter. — In-fact nucleons are made of different combinations of 3 quarks, of which only two of the quarks can be of the same type. 

Combinations of 3 quarks which form into a bound state of material system are known as baryons. We will study about baryons in the last part of this lecture series.

Thus baryons are a naturally occurring collective matter, built from 3 quarks, where the 3 quarks interact among each other, but can’t escape this bound state of formation, even under the impact of tremendous force.

This fact is known as asymptotic freedom, such freedom is only a dream for them, and for us. This is possible in principle, when the distance of separation between them can be made infinite, in order to weaken the existing attractive force between them, to zero.

Physics class tests for junior college, –III

Physics class tests for PUC, ISc, XII in the CBSE, ICSE (CISCE), State boards.
Subject: Physics                                         
Test: Class test — III
Class: PUC — II (also good for ISC — II)
date: 5th August 2013.
Time: 55 minutes 
Total marks: 35

Section A
Objective — 7 questions each carry 1 mark, all questions to be answered.

Question 1
Targets in X-ray tube are made of high atomic number metals. Examples are

A. Tungsten and Platinum              B. Nickel and Chromium

C. Uranium and Plutonium            D. Sodium and Mercury

Question 2
Electric and magnetic fields do not deflect which of the following

A. X-rays                    B. Y-rays

C. Electrons              D. Cosmic Rays

Question 3