Find circumference.
circumference=2pradius=125.7m

How many meters along the track
corresponds to one radian?
| 1rad * | 125.7meters | =20meters |
| 2prad |
NOTE: This should be a common sense answer because the definition of one radian is "the angle subtended when radius equals arc length."

| 125.7meters | * 5.5laps | =691m |
| lap |
| 2prad | *5.5laps | =34.6rad |
| lap |

q=at²/2 = (.5r/s/s)(10s)²/2 = 25rad, or in meters, 25rad*20m/rad=500m

d=s*t = 10m/s*100sec = 1000m
now we can either switch directly to radians (or
we could convert m/s to rad/s and do the problem again, but I wont here)
1000m*1rad/20m = 50 rad
then divide by 2pi to get laps...
50rad* 1 lap/2p = 8 laps
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OnLine an in the 1D Motion Chapter, solve "Circle Displacement".