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Why is glass transparent?

These interactions depend on the nature of the light and the nature of the material. For instance, light falling on a leaf encounters many pigment molecules, predominantly chlorophyll. These molecules absorb light from the red and blue ends of the visible spectrum. The remaining light is scattered back because molecules in a leaf are tightly packed and so, we see …

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Why is Einstein famous?

Albert Einstein is famous for his Theories of Relativity which say that nothing in the universe is absolutely still and that all motion is connected all or comparable. Einstein worked out a method of measuring the speed of moving objects, using the three dimension of space-length, height and thickness-and adding the fourth dimension of time. The three space dimensions tell …

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Why is earthing necessary for electrical appliances?

As it’s a safety factor, earthing is essential and mandatory. It’s an electrical connection between the exposed metallic parts of an electrical appliance or installation and the earth, regarded to have zero potential. Proper earthing provides an alternative and easy path for leakage or faulty current to flow. It ensures that any exposed conductive part of the appliance does not …

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Why is Blue-ray disc black on top?

The Blue-ray disc uses a blue (technically violet) laser operating at a wavelength of 405 nanometre (nm) to read and write data. Conventional DVDs and CDs use red and near infrared lasers, at 650 nm and 780 nm respectively. Because the Blu-ray disc data layer is closer to the surface of the disc, compared to the DVD standard, it was …

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Why is an atom spherical in shape?

When we talk of the shape of an atom, we are referring to the shape of the imaginary volume in which the atom’s electrons orbit. Different electrons orbit at different levels and even at the same level they take different orbits. The shape of the atom depends on several factors, including the and the electrostatic forces between atomic particles. It …

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Why is a transformer core always cubical in shape?

It is not true that cores are always cubical. Current Transformers and Potential Transformers have ringtype cores. Power transformers have cubical cores. The ideal transformer is to have all the magnetic flux produced by one winding linking the other. This is not attained in practical transformers. Flux that does not link both windings is called leakage flux and has the …

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