Physics - Gravitation Question with Solution | TestHub

One night, a boy of height $\mathrm{h}=1.5\mathrm{m}$ is standing on the bank of a straight canal, on the other bank of which a lamp is installed at a height $\mathrm{H}=6\mathrm{m}$ on a pole. There are no ripples on the water surface so light emanated from the lamp, appears as a flare (bright spot) after reflection from the water surface. When the boy starts walking along the bank, the flare appears to him moving at a constant speed $\mathrm{u}=3\mathrm{m}/\mathrm{s}$ relative to the ground. Find speed of the boy. (in m/s)