Examples related to items a) and b) will be discussed,
whereby the dynamically determined spring constant will be
compared with the result of a static measurement. As regards
a), as the pendulum slows down (motion away from the rest
point) and as it speeds up (motion toward the rest point),
inertia forces evolve, which are recorded in addition to the
weight. The maximum accelerations occur at the top turning
point of the swing, the minimum accelerations with maximum
extension of the springs.