Question
Which layer of the earth’s atmosphere reflects
back the radio waves to the earth’s surface?Solution
Long distance propagation of radio waves depends on an invisible layer of charged particles, which envelops the Earth. This layer of charged particles known as the ionosphere has been in existence for millions of years. For those, who pioneered the long-distance radio communication during the early part of the twentieth century, the ionosphere came as a boon.
The altitude of an equilateral triangle is 6√3 cm. Find the area of the equilateral triangle.
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