Accelerated motion – basic principles
How it works
Accelerated motion describes a motion in which the velocity of a body changes. The magnitude of the velocity may change, or its direction. The acceleration a indicates how strongly the velocity changes per unit time: a = Δv/Δt. It is a vector quantity and is caused by a resultant force. For rectilinear motion with constant acceleration, the following relationships apply: v = v₀ + a·t and s = s₀ + v₀·t + 0.5·a·t². If a body starts from rest at the position s₀ = 0, this simplifies to v = a·t and s = 0.5·a·t². In free fall without air resistance, the acceleration is approximately constant and directed downward.
Acceleration means a change in velocity per unit time. With uniform acceleration, a is constant; then one can calculate with v = v₀ + a·t and s = s₀ + v₀·t + 0.5·a·t². Whether a body becomes faster or slower depends on how the acceleration is directed relative to the direction of motion.
An example
A car travels at 10 m/s and accelerates uniformly in 5 seconds to 30 m/s. What is the acceleration?
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50 Exercises
To the learning unit →Own explanation and own practice exercises by AmyMath. Subject reference framework: Physics. The topic assignment may vary by federal state.