Question

A ladder is supported at the height of 30m by the wall. The ladder makes an angle of 60 degree with the ground. A worker starts climbing the ladder at a speed of 2m/s. What is the time taken by him to climb up the ladder?

Answer 1

so sinФ = height/hypotenuse 
     sin60 = 30/ hy
    √3/2 = 30 / hy 
   hy = 60/√3 m is the height of the ladder

so time taken = 60/√3 / 2 = 30/√3 = 10√3 s = 17.32 sec