Question

A ladder is placed against a vertical tower. If the ladder makes an angle of ${30}^{\circ }$ with the ground and reaches up to a height of $15m$ of the tower; find length of the ladder in cm.

• A. 2311
• B. 3000
• C. 1688
• D. 1200

Answer 1

Answer: (B)

3000

Consider the ladder and wall system as the right angled triangle, such that length of wall (W) till the ladder reaches be the perpendicular= 15 cm and angle (G) made by ladder (L) with the ground is ${30}^{\circ }$,
and length of ladder be the Hypotenuse.
Thus, $\sin G=\frac{P}{H}$
$\sin 30=\frac{W}{L}$
$\frac{1}{2}=\frac{15}{L}$
$L=30m=3000cm$