A mechanical system consists of two gears, Gear A and Gear B, in mesh as shown in the diagram. A lever of length L=50 cmL = 50\text{ cm}L=50 cm is attached coaxially to the axle of Gear A.
Gear A has a radius RA=20 cmR_A = 20\text{ cm}RA=20 cm, and Gear B has a radius RB=8.0 cmR_B = 8.0\text{ cm}RB=8.0 cm. A student applies a constant force of F=60 NF = 60\text{ N}F=60 N perpendicular to the end of the lever to rotate Gear A.
Assuming 100% efficiency in the transmission of torque, what is the magnitude of the moment (torque) transmitted to the axle of Gear B?
4.8 N m4.8\text{ N m}4.8 N m
12 N m12\text{ N m}12 N m
30 N m30\text{ N m}30 N m
75 N m75\text{ N m}75 N m