Mechanics Problem 2

I like simple mechanics problems that illuminate fundamentals. An example is shown in the schematic diagram above. 

A small block of mass m₁ is released from rest at the tip of an inclined plane of a wedge of mass m₂. The wedge base has a length d and the incline has an angle θ. The small block slides on the incline and eventually reaches its bottom. The wedge will slide to the left as the small block slides.

Neglecting friction, determine the speed of the wedge when the small block reaches the bottom of the inclined plane.

Hint: This problem requires you to use conservation of momentum and conservation of energy, in addition to understanding inertial reference frame. An alternative way is to use Newton's second law and to use a clever kinematic constraint.