Thrusts

Thrust is a force that moves an object in a specific direction. In physics, thrust is a reaction force described by Newton's third law that occurs when a system accelerates mass or directs a flow of fluid backward. The plural "thrusts" can refer to multiple instances of such force or to different contexts in which thrust is relevant.

In propulsion, thrust is the net forward force produced by engines, jets, propellers, or rockets. It results from accelerating propellant mass rearward and is affected by the mass flow rate, exhaust velocity, and pressure changes in the nozzle. Practical thrust is measured in newtons or kilonewtons and may be expressed as static thrust (at zero forward speed) or dynamic thrust during flight or ascent.

Thrust is a central parameter in performance metrics such as thrust-to-weight ratio, which compares available thrust to the vehicle's weight. This ratio influences takeoff performance, climb rate, and acceleration for aircraft and spacecraft. Efficiency and propulsion design balance thrust with fuel consumption and mass.

Outside propulsion, "thrust" also appears in other domains. In fencing and many martial arts, a thrust is a straight forward stab delivered with a blade. In geology, thrusts refer to thrust faults, low-angle reverse faults formed under compressional forces that push rock masses over others, a common feature in mountain belts.