NTA Abhyas JEE Main2020MathematicsHeights and DistancesPractice
The tops of two poles of height 40 m and 25 m are connected by a wire of length 30 2 3 - 1 m . If the wire makes an angle α with the horizontal, then the value of 2 sin α is equal to (take, 3 = 1 . 7 )
Correct answer
0.35
Step-by-step solution
Let, A B = 40 and C D = 25 be the two poles. A C = l is the length of the wire. C E is the horizontal through C and ∠ A C E = α A E l = sin ⁡ α ⇒ l = 15 sin ⁡ α = 30 2 3 - 1 ⇒ sin ⁡ α = 3 - 1 2 2 Hence, 2 sin α = 0 . 35