Is there such a thing as ft-k being a unit of force? Where k=1000 lbs?
In other words, the following is a calculation on impact. I don't follow the conversion of Joules to Force. This is not homework, this is someone trying to tell me that ft-k is units of force and not energy. What am I missing? What kind of force is "ft-k"?

80 ton truck at 70 mph on impact:

Wnet = Kf – Ki= ½*mv^2

W [Work]= ½*mv^2

m=mass; kg

v= Speed; meter/sec

W=(½) (80*1016)*(70*1.609*1000/3600)^2=39,779,275 Joules (This is "Work")

1 Joule≈0.73756 ft-lb

F [Force]=39,779,275*0.73756/1000=29,340 ft-k

If: ft meaning feet (SI: meters) and lbs meaning force-pounds (SI: Newtons)
Then that's a unit of energy.

Of course, I may be misunderstanding what your asking. Could you clarify?

EDIT: seeing Dragon's; yes, that could be torque too.
-Andrew

This is getting way out of my field of building engineering, but I don't see how that calculation got from energy of impact on a rigid object into a torque on that object. Torque is force times distance, I always have thought of as different from a "force" (kips, lbs etc).

Yes, it is ft (SI meters) and lbs (SI newtons). I am starting to realize the guy that did the calculation doesn't know what he is doing.

What am I missing? What kind of force is "ft-k"?
Your "ft-k" is not a force. It is energy. Energy and force are related but distinct physical quantities. For one thing, force is vectorial while energy is scalar. For another, as you noted, they have different units.

sure its torque
Not in the case described in the OP. Torque (\mathbf r \times \mathbf F) and kinetic energy (1/2mv^2) do have the same primitive units (mass*length2/time2). However, torque is inherently a vectorial quantity (more specifically, it is a pseudo-vector) while energy (or work) is a scalar quantity. Just as force is related to work (energy) via W=\int \mathbf F\cdot d\mathbf r, torque is related to work via W=\int \mathbf \tau \cdot d\mathbf \theta. Exactly one joule of energy must be expended to apply a constant force of one newton to some object as it moves a distance of one meter. Similarly, exactly one joule of energy must be expended to apply a constant torque of one newton-meter to some object as it rotates through an angle of one radian.

thanks