Can a gravity driven machine be built such that it accelerates an object faster than freefall?

Question

It seems counterintuitive, but so are DDWFTTW carts.  It may be possible, since if speed is increased, so too is the power provided by gravity Fds/dt.

Imagine this device vertically constrained:  https://www.youtube.com/watch?v=k-trDF8Yldc 
with a very heavy ruler.  The cart should shoot down faster than g right?  It seems like there must be some constraint, e.g. that the center of mass can't fall faster than freefall, but I'm not certain.

Andrew Smith · Accepted Answer

Your statement is correct.  The CENTRE OF GRAVITY may not fall faster than g.
A machine can accelerate a small object faster than g if a heavier object falls slower than g.
See a trebuchet for an example.

ignoramus · Answer

Gravity would not be driving the cart.  It has a power source - the heavy ruler, and a gearing system - the large wheel driving the small ones.  Aircraft can dive faster than the speed of sound if they want to.  But they AIN'T "falling".

Be an Angel · Answer

A lever would do this.  Drop a big thing on the short side, the thing on the long side, that weighs less goes up much faster.

Mr. P · Answer

Yes by a simple 2 to 1 pulley system. Thus if one weight is moving in freefall, then the end will be moving in 2x freefall.

Skoda John · Answer

Yes.
If you use gearing.

Can a gravity driven machine be built such that it accelerates an object faster than freefall?

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