How a simple pendulum inside a running elevator oscillates

We propose to effectively realize a time-dependent gravitational acceleration by using a running elevator, so that a simple pendulum inside it effectively becomes one with a time-dependent gravitational acceleration. We did such an experiment using a realistic elevator, and analyzed the data. The acceleration of an elevator is much smaller than the gravitational acceleration, and is time-dependent only when the elevator starts and stops. However, we have managed to establish the effect on the oscillation of the pendulum. The effect becomes pronounced if the simple pendulum is put in a container vertically accelerating, and the acceleration is time-dependent, while its magnitude is comparable with that of the gravitational acceleration.