A radar has a power of … and is operating at a frequency of … … It is located on a mountain top of height … … The maximum distance upto which it can detect object located on the surface of the earth (Radius of earth …) is :

Option A. Let … is the maximum distance, upto it the objects

Communication Systems

JEE Main 2012 · Annual, Paper 1 · Q6302

PhysicsMedium79×since 2003Q6302

A radar has a power of

1kW

and is operating at a frequency of

10

GHz.

It is located on a mountain top of height

500

m.

The maximum distance upto which it can detect object located on the surface of the earth (Radius of earth

= 6.4 \times {10^6}m

) is :