Question

43. (1) Here ( A C ) is the ladder, ( A B ) is the height of the wall which is required and ( B C ) is the distance of ladder foot from wall. Now in triangle ( Delta A B C )
[
sin theta=frac{A B}{A C} Rightarrow sin 30^{circ}=frac{A B}{20}
]
[from Trigonometric ratio ( left.sin 30^{circ}=frac{1}{2}right] )
[
frac{1}{2}=frac{A B}{20} Rightarrow A B=10
]

# 43. A ladder 20m long is leaning against a vertical wall. It makes an angle of 30° with the ground. How high on the wall does the ladder reach? RRB NTPC (Phase I) 2016 (1) 10 m (2) 17.32 m (3) 34.64 m (4) 30 m

Solution