Explanation:
Wind energy, or wind power, is created using a wind turbine, a device that channels the power of the wind to generate electricity. The wind blows the blades of the turbine, which are attached to a rotor. The rotor then spins a generator to create electricity . Wind energy is a renewable energy source that is clean and has very few environmental challenges. Wind power actually starts with the Sun. In order for the wind to blow, the Sun first heats up a section of land along with the air above it. That hot air rises since a given volume of hot air is lighter than the same volume of cold air. Cooler air then rushes in to fill the void left by that hot air and voila: a gust of wind. The Office of Energy Efficiency and Renewable Energy describes a wind turbine as “the opposite of a fan.” Simply stated, the turbine takes the energy in that wind and converts it into electricity. So how does it do that? First, the wind applies pressure on the long slender blades, usually 2 or 3 of them, causing them to spin, much like the wind pushes a sailboat along its path through the water. The spinning blades then cause the rotor, or the conical cap on the turbine, and an internal shaft to spin as well at somewhere around 30 – 60 revolutions per minute. The ultimate goal is to spin an assembly of magnets in a generator which will, well, generate voltage in a coil of wire thanks to electromagnetic induction. Generators require faster revolutions, however, so a gear box typically connects this lower speed shaft to a higher speed shaft by increasing the spin rate to around 1000 to 1800 revolutions per minute. These gear boxes are costly as well as heavy, so engineers are looking to design more “direct-drive” generators that can work at the lower speeds.
Answer:
30
Explanation:
The seed of an angiosperm is formed as a result of fertilization (fusion of sperm in pollens and the ova from ovary). According to the question, the cells of the seed which will grow into the plant contains 20 chromosomes. Seeds of angiosperms contain a tissue called ENDOSPERM that forms as a result of the unique DOUBLE FERTILIZATION in angiosperms. It occurs when one haploid sperm cell fuses with two haploid polar nuclei to form a triploid endospermic structure that serves as food for the growing embryo in the seed.
Now based on the above explanation, the diploid plant cell with 20 chromosomes will have 10 chromosomes (half as much) in its gametes as a result of meiosis. This 10 chromosomes in each gamete (sperm and ovum) fuses to form a diploid zygote with 20 chromosomes, while one haploid sperm cell (10 chromosomes) also fuses with two haploid polar nuclei (10 chromosomes each) to form a triploid endosperm with 30 chromosomes i.e. 10+10+10.
I believe the answer would be “B” Srry not good with science
