A ladder makes an anglesof `60^(@)` with the ground when placed against a wall. If the foot of the ladder is `2m` away from the wall, the length of the ladder is

Options

A. `4/(sqrt(3)) m`
B. `4sqrt(3)m`
C. `2sqrt(2) m`
D. `4 m`

Answer

D

Explanation

Let AB be the ladder and BC be the wall.
Then, `angleCAB = 60^(@)` and `CA = 2m`.
Let AB = x metres. Then,
`(AC)/(AB) = cos 60^(@) = 1/2 rArr 2/x = 1/2`
`rArr x= 4`.