1. So, what we're going to study now is what's called small oscillations, or simple harmonic motion.

2. To a first approximation, the motion in a normal vibration can be described as a kind of simple harmonic motion.

3. Anharmonic oscillation is defined as the deviation of a system from harmonic oscillation, or an oscillator not oscillating in simple harmonic motion.

4. Vibration test: The battery is rigidly clamped to the platform of a vibration machine and a simple harmonic motion having an amplitude of 0,8 mm (1,6 mm maximum total excursion) is applied.