Question

The angle of elevation of an aeroplane from
a point P on the ground is 60°. After 12
seconds, the angle of elevation changes to 30°.
If the plane is flying horizontally at a speed
of 600/3 km/h, find the height at which it is
flying​

Answer 1

HERE IS YOUR ANSWER

Let A be the position of the plane, and it moves towards C. Let BP=x. Time taken by plane to reach C is 12s=

60×60

12

hr

Distance=Speed×Time

AC=600

3

×

60×60

12

=2

3

km

In △ABP,

BP

AB

=tan60

∘

⟹

x

AB

=

3

x=

3

AB

From figure, BD=AC=2

3

km

PD=PB+BD=

3

AB

+2

3

=

3

AB+6

km

In △CDP,

PD

CD

=tan30

∘

3

AB+6

AB

=

3

1

3AB=AB+6

AB=3 km. This is the height of the plane.

solution

PLEASE MARK AS BRAINLIEST