Ke trans+ ke rotatational

1. Mar 9, 2006

alex_boothby

when i add ke translational + ke roatational, i dont get potential which i should, although i was wondering if maybe it was due to slipping although i thought it would still be closer than i got

does this sound right?

ke trans(0.002520831)+ke rotational (0.001008332) = 0.003529163
and
pe=0.014278472

as you can see not very near it!

is this right or have i gone wrong?

the exp was rolling a ball bearing down a 5 degree slope and these calcs were from the 1m release mark. the radius is 0.00765m

thanks

to get the angular speed i used linear V/R (radius)

i got linear v by divinding distance by time.

2. Mar 9, 2006

topsquark

If you are rolling a ball down a slope, the linear v will NOT be d/t because the ball is accelerating. d/t is average speed not instantaneous speed, which is what you need for your equations.

-Dan