Accelerationrelated

Acceleration-related refers to phenomena, quantities, and notions that involve acceleration—the rate at which velocity changes over time. In physics, acceleration is a vector: it has magnitude and direction, denoted a, and its SI unit is meters per second squared (m/s^2). Instantaneous acceleration is the derivative of velocity with respect to time, a = dv/dt, while average acceleration over a time interval is Δv/Δt.

In kinematics, constant acceleration leads to simple equations of motion: v = v0 + a t and s = s0 + v0 t + 1/2 a t^2, with the relation v^2 = v0^2 + 2 a (s − s0). Acceleration can be decomposed into components along the path: tangential acceleration a_t = dv/dt, and a centripetal (or radial) acceleration a_c = v^2/r toward the center of curvature in circular motion.

In relativity, the distinction between coordinate acceleration and proper acceleration is important; proper acceleration is what an accelerometer measures and is invariant, while coordinate acceleration depends on the reference frame. Gravitational acceleration, often denoted g, is the acceleration due to gravity near a massive body; near Earth it is about 9.81 m/s^2 downward.

Applications and measurement: accelerations are measured with accelerometers in devices such as smartphones, vehicles, and aircraft. High accelerations relate to G-forces and can impact safety and comfort; jerk (the rate of change of acceleration) influences ride quality and structural design. Acceleration concepts also appear in biomechanics, sports science, and engineering analyses.