Final answer:
The force from the second piston can be calculated using Pascal's Law by multiplying the pressure exerted on the brake piston by its area.
Step-by-step explanation:
The force from the second piston can be calculated using Pascal's Law.
Pascal's Law states that pressure exerted on a fluid is transmitted equally in all directions.
In this case, if the master cylinder piston applies a pressure P to the brake piston, which has twice the square area, then the force from the second piston can be calculated by multiplying the pressure by the area of the brake piston.
Let's say the area of the master cylinder piston is A, and the area of the brake piston is 2A. If the pressure exerted by the master cylinder piston is P, then the force from the second piston can be calculated as F = P * 2A.