Question

The angle of elevation of the top of a tower from a point P on the ground is alpha degree. After walking a distance d towards the foot of the tower , angle of elevation is found to be beeta degree. Then

(A)alpha degree < beeta degree (B)alpha degree > beetadegree (C) alpha degree = beetadegree (D) none of these

Answer 1

Answer:

Option (B) is correct

Step-by-step explanation:

Answer 2

For the given situation angle (A) alpha < beeta.

Explanation:

• For a given right angled triangle having perpendicular length 'p', the base length 'b' and the angle opposite to the perpendicular side 'A' we have,      $tan A=\frac{p}{b}$    
• In the given situation let the length of the tower be 'l' and the distance from its foot to the point P be 'x' and angle of elevation be $\alpha$. Hence,                   $tan\alpha=\frac{l}{x}$   ---(a)
• Now as we walk a distance 'd' towards the foot of the tower the base length of the new right angled triangle will be $x-d$ and the angle of elevation from the new point is $\beta$ hence,   $tan\beta=\frac{l}{x-d}$  ---(b)
• Now since, $x>x-d$ from (a) and (b) we get, $\beta>\alpha$ .