Environmental Issues: Class 12

Environmental Issues: Odum defined pollution as, ‘undesirable change in physical, chemical and biological properties of air, water, and soil, which directly or indirectly affect human beings’. The basic cause of…

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Ecosystem: Class 12

The ecosystem is a self-regulatory and self-sustaining structural and functional unit of landscape (biosphere) consisting of a community of living beings and the physical environment, both interacting and exchanging materials…

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Organisms and Populations: class 12

Organisms and Populations: The term ‘ecology’ is derived from two Greek words-Oikos means ‘house or place to live’ and logos means ‘a discussion or study’. The German biologist Ernst Haeckel…

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Electromagnetic Waves: class 12

Displacement Current: The current which comes into play in the region, wherever the electric field and hence the electric flux is changing with time. Ampere’s circuital law for conduction current…

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Alternating Current: class 12

Alternating Current: It is that current which changes continuously in magnitude and periodically in direction. It can be represented by a sine curve or a cosine curve. It changes direction with…

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Electromagnetic Induction

Electromagnetic induction: It is the phenomenon of generating an emf by changing the number of magnetic lines of force (i.e. magnetic flux) associated with the circuit. The emf so generated…

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