Physics

Aluminium being a good conductor of heat conducts away the heat from the substance quite easily and causes quick freezing.

The unit of force is a derived unit.

In a Cinema hall, the distance between the projector and the screen is increased by 2%. Then the intensity of illumination on the screen is decreased by 4%.

Solar energy is any type of energy generated by the sun. Solar energy is created by nuclear fusion that takes place in the sun. Fusion occurs when protons of hydrogen atoms violently collide in the sun’s core and fuse to create a helium atom.

The electrical domestic tube light gives white fluorescent light because of falling of ultra violet rays on the white inner coating of the tube. The ultraviolet rays have high frequency and shorter wavelength are converted to visible white light with lower frequency and greater wave length.

A shock absorber is a mechanical device designed to smooth out or damp shock impulse, and dissipate kinetic energy. Steel is an alloy made by combining iron and other elements, the most common of these being carbon. When carbon is used, its content in the steel is between 0.2% and 2.1% by weight, depending on the grade. Varying the amount of alloying elements and the form of their presence in the steel (solute elements, precipitated phase) controls qualities such as the higher elasticity, hardness, ductility, and tensile strength of the resulting steel.

The boiling point of water is lower at higher altitudes due to the decreased atmospheric pressure. A liquid boils when its vapour pressure exceeds the local total pressure. As the atmospheric pressure drops, the Vapour pressure increases more than the local pressure at an even lower temperature.

Old postcards, books, signs, photos and other paper products made before the late 1930s rarely glow under a black light. Chemical bleaches and dyes used in modern papers will fluoresce under ultraviolet light. Knowing this helps to detect forged documents and distinguish reproductions in all types of ephemera.

The slope of a velocity graph represents the acceleration of the object. So, the value of the slope at a particular time represents the acceleration of the object at that instant.

Coal is a non renewable source of energy.