Multiple choice

Two poles P and Q of equal height are standing in a plane. The distance between the poles P and Q is 100 m. The respective angles of elevation of the top of the poles P and Q from a point on the ground, lying between both poles, are 60o and 30o respectively. If the height of the poles is h and the distance of the point from the pole P is x, then find the values of h and x. (Take √3 = 1.732)

  1. h = 40 m and, x = 25 m

  2. h = 43 m and, x = 20 m

  3. h = 43.3 m and, x = 25 m

  4. h = 40.3 m and, x = 35 m

  5. h = 40.3 m and, x = 2.5 m
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let height be h. tan(60) = h/x => h = x*sqrt(3). tan(30) = h/(100-x) => h = (100-x)/sqrt(3). Equating: x*sqrt(3) = (100-x)/sqrt(3) => 3x = 100 - x => 4x = 100 => x = 25. h = 25 * 1.732 = 43.3 m.

Keep practicing — related questions