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A air-force plane is ascending verticall...

A air-force plane is ascending vertically at the rate of 100 km/h. If the radius of the earth is r km, how fast is the area of the earth, visible from the plane, increasing at 3 min after it started ascending?
Note Visible area `A=(2pir^(2)h)/(r+h)`, where h is the height of the plane above the earth.

Text Solution

Verified by Experts

The correct Answer is:
`(200pi^(3))/((r+5)^(2))km^(2)//h`
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