Dhaka College: The Department of Physical Science

Prof. Dr. Md. Nazrul Islam, Head of the Department of Physics Science Dhaka College

Honours course in Physics Department in Dhaka College started in 1977 and the founder Head of the Department was Md. Abul Hashem (Associate Professor). There were only 25 students in the first batch. But the number of students are increasing every year; and at present 120 students are enrolled in each session under NationalUniversity. The first batch of Masters Final Year students was enrolled in this department in 1980 . Now there are 95 students in current M. Sc session. At present total students of the department are about 400. The number of teachers in this department is  19 as well as there are 5 non teaching staffs.

Hon’able teachers serving here

w       Professor & Head of the Department

1.       Dr. Md. Nazrul Islam

w       Associate Professor

1.       Md. Alauddin Sarker

3.       Md. Humayun Kabir

5.       Md. Abdul Gafur

4.       SK. Sabbir Ahamed

w       Assistant Professor

1.       Sharmin seema

2.       Md. Anisur Rahman

3.       Md. Nasiruddin

4.       Abul Hasnat Masum Iquebal

5.       Md. Shahin Uddin

w       Lecturer:

1.       Md. Nurul Amin Khan

2.       Md. Momanul Islam

3.       Rokeya Sultana

4.       Jewel Roy

5        Md. Obaidul Karim

w       Demonstrator:

1.       Muhammad Abdur Rouf

2.       Mohammad Habibul Bashar

3.       Mohammad Monirul Islam

Seminar Facilities

In addition to the facility of Dhaka college central library , Department of Physics has its own collection of huge number of books and publications in the seminar. Students and teachers have easy access to it . The students can read during their leisure time and borrow necessary books  showing their seminar cards. A teacher in charge and a staff guide the students to run the seminar smoothly & effectively.

Laboratory Facilities

There are 4 laboratories in this department for the students of different classes.There are also two specialized labs to conduct the optical and electronics experiment. These labs are well-equipped with various scientific instruments.

Force in various Dimension

Color Force

A property of quarks labeled color is an essential part of the quark model. The force between quarks is called the color force. Since quarks make up the baryons, and the strong interaction takes place between baryons, you could say that the color force is the source of the strong interaction, or that the strong interaction is like a residual color force which extends beyond the proton or neutron to bind them together in a nucleus.

Inside a baryon, however, the color force has some extraordinary properties not seen in the strong interaction between nucleons. The color force does not drop off with distance and is responsible for the confinement of quarks. The color force involves the exhange of gluons and is so strong that the quark-antiquark pair production energy is reached before quarks can be separated. Another property of the color force is that it appears to exert little force at short distances so that the quarks are like free particles within the confining boundary of the color force and only experience the strong confining force when they begin to get too far apart. The term “asymptotic freedom” is sometimes invoked to describe this behavior of the gluon interaction between quarks.

Fundamental Forces

A force which can hold a nucleus together against the enormous forces of repulsion of the protons is strong indeed. However, it is not an inverse square force like the electromagnetic force and it has a very short range. Yukawa modeled the strong force as an exchange force in which the exchange particles are pions and other heavier particles. The range of a particle exchange force is limited by the uncertainty principle. It is the strongest of the four fundamental forces.

Since the protons and neutrons which make up the nucleus are themselves considered to be made up of quarks, and the quarks are considered to be held together by the color force, the strong force between nucleons may be considered to be a residual color force. In the standard model, therefore, the basic exchange particle is the gluon which mediates the forces between quarks. Since the individual gluons and quarks are contained within the proton or neutron, the masses attributed to them cannot be used in the range relationship to predict the range of the force. When something is viewed as emerging from a proton or neutron, then it must be at least a quark-antiquark pair, so it is then plausible that the pion as the lightest meson should serve as a predictor of the maximum range of the strong force between nucleons.

The sketch is an attempt to show one of many forms the gluon interaction between nucleons could take, this one involving up-antiup pair production and annililation and producing a ?- bridging the nucleons.