Part A:
To answer this item, we need to convert the given revolutions per minute in speed expressed as miles per hour. In order to do so, we need to use the dimensional analysis and the appropriate conversion factor.
We calculate the circumference that is covered by the wheel.
C = πD
where C is the circumference and D is the diameter.
Substitute the known values,
C = π(26 in) = 81.68 inches
The speed tested is calculated below.
s = (81.68 inches/rev)(480 rev/min)(1 mil/63360 inches)(60 min/1 hr)
s = 37.127 mil/h
ANSWER: 37.127 mil/h
Part B:
Similar to what was done in Part A, the setting of the balancer is calculated below,
setting = (80 mil/h)(1h/60 min)(63360 in/1 mil)(1 rev/81.68 in)
setting = 1034.23 rev/min
ANSWER: 1034.23 rev/min