Railway Science (Physics-Miscellaneous)

Silicon, a semiconductor, is commonly used due to its properties. Solar cells convert light energy into electricity through the photovoltaic effect. Cesium, with its low ionization energy, is also utilized for efficient sunlight conversion.

Solar Cell (Photovoltaic cell): Electronic device that converts the energy of light directly into electricity by the photovoltaic effect. The Photovoltaic effect is the generation of voltage and electric current in a material upon exposure to light. Edmond Becquerel in 1839 was the first to demonstrate the photovoltaic effect experimentally.

Nitrogen gas is an anti-oxidant, which prevents oxidation of fat and oil molecules. Another reason that nitrogen gas is often used for food packaging is to provide a pressurized atmosphere that prevents package collapse.

Hardness: It is the property of matter to maintain its shape even if external force works on it and solids show this property. Fluidity: It is the property of a substance to easily flow and allow a change in its shape under external forces and this property is exhibited both by liquids and gasses.

Fluidity: It is the property of a substance to easily flow and allow a change in its shape under external forces and this property is exhibited both by liquids and gasses.

Compressibility - The property due to which the particles of matter can be compressed or reduced in volume by applying force or pressure. Compressibility factor (Z) - The ratio of the molar volume of a gas to the molar volume of an ideal gas at the same temperature and pressure. Rigidity - It is the property which helps a substance to retain its shape when force is applied to it.

Density: The density of a substance (ρ) is defined as the ratio of its mass (M) to its volume (V). Formula: Density =  𝑀/v . The relative density is defined as the ratio of the density of the substance to the density of water at 4°C. The density of water is maximum at 4°C. Kinetic Energy of an object is the form of energy that it possesses due to its motion. Formula : 1/2 × mass × (velocity)².

Rigidity is a physical property of solids that describes its ability to resist change in shape when an external force is applied. It is a measure of how much a material resists being stretched or compressed.

The SI unit of density is kg/m³ . Mathematically, it is expressed as
𝑀𝑎𝑠𝑠/𝑉𝑜𝑙𝑢𝑚𝑒. Kinetic energy - SI unit is Joule (J). Formula: 1/2 mv².

Any objects experience a force of buoyancy when they are immersed in a fluid. The magnitude of this buoyant force depends on the density of the fluid.