- Power (Hits: 5859)
- Power System (Hits: 162)
- Pressure (Hits: 20988)
- Pressure Loss (Hits: 665)
- Pressure Vessel (Hits: 4317)
- Project Management (Hits: 1935)
- Projectile (Hits: 1566)
- Pulsation and Vibration (Hits: 361)
- Pump (Hits: 6864)
- Quadrilateral (Hits: 820)
- Quantum Mechanics (Hits: 351)
- Radiation (Hits: 561)
- Rectangle (Hits: 390)
- Refinery (Hits: 635)
- Relativity (Hits: 375)
- Reservoir (Hits: 518)
- Resistance (Hits: 542)
- Rotating Equipment (Hits: 357)
- Rotational (Hits: 564)
- Roughness (Hits: 1010)