পদার্থ বিজ্ঞান

Physics

1. Heat

Heat and temperature-(Definition and difference). Unit of heat. Celsius, Fahrenheit scale of temperature and numerical examples on conversion.

Factors determining the quantities of heat-Idea of specific heat. Unit-cal/gm/°C, principle of calorimetry. Definition of thermal capacity and water equivalent. Simple numerical examples;

2. Light Lens & Dispersion

Lens-Convex and concave, optical centre-Focussing action and focalj length, linear magnification, distinction between real and virtual images;

Formation of magnified real and virtual images by a convex lens magnifying glass

Dispersion of light-Definition, dispersion of white light by a prism.

Spectrum-Pure and impure (distinction only).

3.Current Electricity & Electromagnetism

Current-charges in motion

Concept of emf, potential difference-Ohm’s Law and resistance; units of current, emf and resistance, dependence of resistance on length and cross-section, resistances in series and parallel, simple problems.

Demonstration with dry batteries, resistances, torch-light lamps and j switch.

Heating effect of current-Joule’s law with practical application to heater and electric iron; Electrical power and energy, household consumption.

Household circuits-switches, fuses, three-pin plugs, earthing, colour coding of wires.

Magnetic effect of current, Ampere’s swimming rule. Action of magnet on current, Fleming’s left hand rule. Burlow’s wheel and application in case of a motor, electromagnet-its strength and use; use of voltameter and ammeter.

4. Modern Physics

Thermionic emission (Basic idea-no analytical details) and hot cathode ray tube; diode valve (Principle only).

Principle of production of X-rays-properties and uses.

Natural Radioactivity-the nature of \alpha ,\beta and \gamma rays, (charge and mass), penetrating power; radioactivity-a nuclear phenomenon, hazards and safety precautions.

Simple idea of fission, fusion (only qualitative idea).

***