Wind Mill

The blades of a windmill sweep out a circle of area A. (a) If the wind flows at a velocity upsilon perpendicular to the circle, what is the mass of air passing through it in time t? (b) What is K.E. of the air ? (c) Assume that the wind mill converts 25% of the wind's energy into electrical energy , and that A=30m^(2), upsilon=36km//h and the density of air is 1.2kg//m^(3) . What is electrical power produced ?

Look at the activites listed below. Reason out whether or not work is done in the light of your understanding of the term 'work'. (a) Suma is swimming in a pond. (b) A donkey is carrying a load on its back. (c ) A wind -mill is lifting water from a well. (d) A green plant is carrying out photosynthesis. (e ) An engine is pulling a train. (f) Food grains are getting drired in the Sun. (g) A saliboat is moving due to wind energy.

The first Cotton Mill in India was set up as a spinning mill in 1854 in _______.

Where was the first Cotton Mill in India established ?