Question

A RADAR spots an enemy plane. A radio pulse emitted by the radar and reflected by the
plane reaches back in 2x10-4
s. Find the distance between the enemy plane and RADAR.
(Speed of radio pulse = 3x108
s) with equations

Answer 1

By the given data

    time = t = 2*10'-5 s

    speed = v = 3*10'8 m/s

According to the distance formula

             S=v t

Putting the values

    S= (3*10'8)(2*10'-5)

       = 6*10'3

So, the aeroplane is 6*10'3 m away.

Answer 2

Answer:

Given

Total time taken by radar signal,t=0.5×10−3 sec

speed of pulse , v = 3×108 m/s

Total distance travelled by pulse, x=v×t=3×108×0.5×10−3=1.5×105m

Therefore, distance of plane from ship is x/2=7.5×10^4 m