Final answer:
The correct term for one brake shoe applying force to a second brake shoe is 'servo action', which allows for more efficient braking in automotive drum brakes.
Step-by-step explanation:
The action described where one brake shoe indirectly applies force on a second brake shoe is most accurately referred to as servo action. In automotive drum brakes, servo action occurs when the primary brake shoe is pressed against the rotating drum, and it in turn pushes on the secondary brake shoe, creating a self-enhancing braking effect. This servo action allows for more efficient braking since the motion of the drum contributes to the force applied on the second shoe.