Question

what will be the angle of elevation of the sun when the length of a shadow of a vertical Pole is equal to its height

Answer 1

In right angle ΔABC, AB represents the vertical pole and BC represents the shadow on the ground.θ represents angle of elevation the sun.
tan θ = h / x
But length of shadow = height of the tower, i.e. h = x.
tan θ = h/ h = 1
tan θ = tan 45°
θ = 45°
Thus, angle of elevation of the sun = 45°.