Questions

The Chipko movement. In the 1970s, an organized resistance to the destruction of forests spread throughout India and came to be known as the Chipko movement. The name of the movement comes from the word 'embrace', as the villagers hugged the trees, and prevented the contractors' from felling them.

Semiconductors are the basic materials used in the present solid state electronic devices like diode, transistor, ICs, etc. 2. Lattice structure and the atomic structure of constituent elements decide whether a particular material will be insulator, metal or semiconductor. Semiconductors are elemental (Si, Ge) as well as compound (GaAs, CdS, etc.). Silicon, Germanium, Gallium Arsenide are semiconductors, but Quartz is an insulator.