(Solved): Problem (7) A gear set has a module of 5mm, a 20 pressure angle, and a 24-teeth cast-iron ...

Problem (7) A gear set has a module of $$5\mathrm{mm}$$, a $$20^{?}$$ pressure angle, and a 24-teeth cast-iron spur pinion driving a 48-teeth cast-iron gear. The pinion is to rotate at $$50\mathrm{RPM}$$. If the permissible bending stress is limited to $$690\mathrm{MPa}$$ and face width $$=60\mathrm{mm}$$, find the horsepower input which can be used with this gear-set, if the gears are: a. Spur gears b. Helical gears, with helix angle $$=20^{?}$$