For the countershaft in Prob. 3–72, p. 138, assume the gear ratio from gear B to its mating gear is 2 to 1.
(a) Determine the minimum number of teeth that can be used on gear B without an interference problem in the teeth.
(b) Using the number of teeth from part (a), what diametral pitch is required to also achieve the given 8-in pitch diameter?
(c) Suppose the 20◦ pressure angle gears are exchanged for gears with 25◦ pressure angle, while maintaining the same pitch diameters and diametral pitch. Determine the new forces FA and FB if the same power is to be transmitted.