alternation of generations in gymnosperms

. Gymnosperms are heterosporous, producing two kinds of spores microspores and megaspores produced by separate sporangia. The two types of sporangia - microsporangia and megasporangia are found on special leaf like structures called sporophylls. The microsporangia represent the pollen sac..

Alternating Currents..

Direct Current and Alternating Current - If the current flows always in the same direction, it is called 'direct current'. Direction current is represented as DC or dc. The current derived from a cell or a battery is direct current - since it is unidirectional. The positive and negative t..

. It is an amazing fact that the charge carriers get this signal of direction change is propagated at the speed of light. What difference does it make if direct current flows or an alternating current flows in a conductor? As far as the heating effects are concerned such as light bulbs an..

An 'AC generator' or 'dynamo' is a machine which produces AC from mechanical energy. Actually, it is an alternator which converts one form of energy into anoth..

An 'AC generator' or 'dynamo' is a machine which produces AC from mechanical energy. Actually, it is an alternator which converts one form of energy into anothe..

The electric generator converts mechanical energy into electrical energy. The two types of generators are DC and AC generators: DC Generators - A cycle dynamo and a car dynamo are examples of DC generators. They produce DC AC Generators..

Electric power is usually generated at places which are far away from the places where it is consumed. At the generating station, the electric power is generated at 11,000 volts. This voltage alternates at a frequency of 50 H..

>Kingdom Mycota exclusively includes the fungi. Fungi are a group of heterotrophic (saprotrophic or parasitic) primitive eukaryotes. Fungal plant body is called mycelium. It may be unicellular and multicellular. The multicellular mycelium forms filamentous structures called hyphae. Fungi reproduce ..

We have seen in the previous lesson that a current carrying conductor when kept in a magnetic field experiences forces and torques. Is reverse phenomenon possible? If we rotate the coil in a magnetic field, will current flow in the coil without we passing it? The answer is yes. Current can be induc..