Experimental percent error in kinetic energy :
(Ki -Kf)/Ki*100% =
My Ki - 128.35 J
Kf = -8.926J - which I am still not sure if it should be negative or positive. This is for a linear track with two carts. First, I determined Velocity from the equation of the line. Then plugged it into the K=1/2mv^2 which gave me 8.9246J - but when you place it into the Ki + Kf = Kt I get a negative.
My question is - do i keep it negative for the (Ki -Kf)/Ki*100% equation - which gives me a 137%. Or do I forget the negative which would give me a 93%. And what does that even mean!!!? I am thinking that the 93% would be the amount lost in kinetic energy?