"The phenomenon of electro-magnetic induction has been technologically important application in the generation of alternating currents." Name the device which can generate alternating currents.

Give one example in which the phenomenon of electromagnetic induction has been technologically exploited?

Draw the various stages of generating an alternating current by a loop[ of wire rotating in a magnetic filed.

What type of life cycle and alternation of generations is seen among pteridephytes? Name the classes of pteridophytes and mention one example each.

What is alternation of generations? Describe how Bryophytes exhibit this phenomenon in their life cycle.

What should be the frequency of alternating 200V so as to pass maximum current of 9A through an inductance of 1 henry.

Though India now has a large base in science and technology, which is fast expanding’ it is still a long way from realizing its potential of becoming a world leader in science. Name some important factors, which in your view have hindered the advancement of science in India.