Just got my head stuck around this question.
Thanks in advance for helping out.
potential energy is converted to kintic energy
mgh = 1/2 mv^2
h = 1/2 (1.4)^2 / 9.8 = .1 meter
THIS h is how far down the bead has fallen.....we must add the .4 position to find the h referenced in the diagram .1 +.4 = .5 m