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In studying some Ballistics concepts...I have ran across the definition of Kinetic Energy thus:

"one half the mass of the body times the square of its speed" or 1/2Mass x Velocity^2

And in ballistics, the KE numbers are measured in FtLbs...and this is what throws me.

I understand that mass can be measured in LBS, but Velocity is not just measured in Feet...but in Feet Per Second! So what the heck happened to the Seconds in the KE result?

Example: 1/2mass of a 10lb cannonball is 5lb, so 1/2M=5lb.

Velocity^2 of it moving at 10fps would be 100fps.

Using the formula for KE we end with a product result of 500FtLb.

HOW did we drop the "seconds" from velocity in the formula result...and why are we not measuring kinetic energy in

**FtLb/second**? (I know this is actually a measurement for "power", so why am I confusing "Kinetic Energy" with "Power"?) How are they different? What happened to the "time factor" in the Energy equasion...if velocity is a part of the formula?

Thanks for ANY clarification.