Which term describes the piston at the upper limit of travel in the cylinder?

Which term describes the piston at the upper limit of travel in the cylinder?

• A. Bottom Dead Center
• B. Top Dead Center
• C. Mid Stroke
• D. Peak Position

Answer: (B)

The piston at the highest point in its travel is called Top Dead Center. This position is one end of the piston’s range in the cylinder, where the piston is closest to the cylinder head and the cylinder volume is at a minimum. At this point the piston’s velocity is momentarily zero as the crank reverses direction, marking the upper limit of travel. The opposite extreme is Bottom Dead Center, where the piston is at the lowest point and the volume is maximum. Mid Stroke would be the halfway point, not the upper limit, and “Peak Position” isn’t standard terminology in this context.

The piston at the highest point in its travel is called Top Dead Center. This position is one end of the piston’s range in the cylinder, where the piston is closest to the cylinder head and the cylinder volume is at a minimum. At this point the piston’s velocity is momentarily zero as the crank reverses direction, marking the upper limit of travel. The opposite extreme is Bottom Dead Center, where the piston is at the lowest point and the volume is maximum. Mid Stroke would be the halfway point, not the upper limit, and “Peak Position” isn’t standard terminology in this context.