Hastighetsförlopp

Hastighetsförlopp refers to how speed changes over time in a moving system. In physics it describes the evolution of an object's speed as time passes, including periods of acceleration and deceleration. If v(t) denotes speed, the rate of change of speed is dv/dt; if velocity v⃗(t) is considered, the instantaneous acceleration is a⃗(t) = dv⃗/dt, and the change in speed is the magnitude of the velocity derivative.

Mathematically, s(t) is the position, v(t) = ds/dt, and a(t) = dv/dt. For constant acceleration a, v(t) = v0 + a t and s(t) = s0 + v0 t + ½ a t^2. When acceleration varies, v(t) is found by integrating a(t).

Representation and measurement: hastighetsförloppet is commonly depicted as a speed–time diagram. The area under the speed curve corresponds to distance traveled (assuming nonnegative speed). In practice speeds are measured with devices such as tachometers, radar, GPS or inertial sensors.

Applications: the concept is used in mechanics, vehicle dynamics, sports science, and biomechanics to analyze performance, control strategies, and safety margins. The form of a hastighetsförlopp depends on the acting forces (propulsion, drag, friction) and object mass, and can be described by differential equations or empirical data. Typical models include linear, piecewise-linear, exponential, or logistic forms depending on the system.