(T) or (F) windmills can do their job all the time as the wind will never stop blowing
false
(T) or (F) both modern wind turbines and old windmills are used to generate electricity
false
take 25 points
25 points
(T) or (F) green houses help farmers to grow the plants that need cold weather
false
the primary source of energy on earth
the sun
a device that uses the kinetic energy of the wind to produce electric energy
wind turbines
a device that consists of black pipes used to heat water depending on solar energy
solar water heater
--------- helps to grow crops that need warm weather
greenhouse
the number of blades in modern wind turbines is ----- than in old wind mills
less than
we use ------- mirrors to cook food using the energy of the sun
concave/ collecting/ converging
give reasons why old people used old windmills
to grind grains
give reasons why we feel warm at night although we cannot see the sun
because the air and all things on earth absorbs the sun's heat and emit it at night
choose: the ---- energy of the sun causes the air movement (chemical - radiant - electrical)
radiant
choose: ---- change the kinetic energy into electric energy. (motors - panels - fans - generators)
generators
Give reasons why generators have important role in power stations
because they change the kinetic energy into electric energy
