FAA Aviation Mechanic General (AMG)Physics, Math and Fluid LinesMedium
A technician is troubleshooting a hydraulic system where a small piston with an area of 1 square inch has a force of 500 pounds applied to it. This piston is connected through hydraulic fluid to a large piston with an area of 10 square inches. What output force does the large piston produce?
- A5,000 lb
- B1,000 lb
- C50 lb
- D500 lb
Show answer & explanationAnswer & explanation
Correct answer: A. 5,000 lb
Pascal's Law states pressure applied to a confined fluid is transmitted equally in all directions. Pressure = Force/Area = 500 lb / 1 in² = 500 psi. Output force = Pressure × Area = 500 psi × 10 in² = 5,000 lb.
Why the other options are wrong
- B. This ignores the correct area ratio between the pistons.
- C. This would result from dividing instead of multiplying the areas.
- D. This is only the input force, not the multiplied output force.
Pascal's Law
Pressure applied to an enclosed fluid is transmitted undiminished in all directions, allowing hydraulic systems to multiply force.
- Pressure = Force ÷ Area
- Force = Pressure × Area
- Small piston force can be multiplied at a larger piston
Memory trick: Small push, big shove — fluid spreads the load.