Kiihtyvyksen

Kiihtyvyys is the Finnish word for acceleration. In physics, acceleration is the rate at which an object changes its velocity. Velocity is a vector quantity, meaning it has both magnitude (speed) and direction. Therefore, acceleration occurs when an object's speed changes, its direction changes, or both.

The standard unit of acceleration in the International System of Units (SI) is meters per second squared (m/s²). Mathematically, acceleration is defined as the change in velocity divided by the time interval over which the change occurs. The formula for average acceleration is a = Δv / Δt, where 'a' represents acceleration, 'Δv' is the change in velocity, and 'Δt' is the time interval.

Acceleration can be positive or negative. Positive acceleration means the object is speeding up in the direction of motion. Negative acceleration, often called deceleration, means the object is slowing down. If an object moves at a constant velocity, its acceleration is zero.

Examples of acceleration include a car starting from rest and moving forward, a ball being thrown upwards and then falling back down, or a planet orbiting a star. The force applied to an object is directly proportional to its acceleration and its mass, as described by Newton's second law of motion (F = ma).