Final answer:
The rate of vibration of an object, or how fast it is moving back and forth, is described by the term 'frequency'. Frequency signifies the number of oscillations per unit time. The time taken for a single oscillation is called the period.
Step-by-step explanation:
The term used to describe the rate of vibration of an object - how fast it is moving back and forth - is called the frequency. This represents the number of oscillations or complete cycles of motion (back and forth movements) that an object makes per unit of time. The higher the frequency, the faster the object is vibrating.
If we take the example of a plucked guitar string, each vibration of the string takes the same time as the previous one, and this is called periodic motion. The time to complete one oscillation (one full cycle of motion) remains constant and is called the period. Frequency and period are related. The faster the vibrations (higher frequency), the shorter the period, and vice versa.
In the absence of friction, the time to complete one oscillation remains constant and is called the period. It's usually measured in seconds, but any convenient unit of time may be used. The term 'period' refers to the time for some event whether repetitive or not, but in the context of oscillatory motion, it is, by definition, repetitive.
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