# Basic Terms Associated with SHM

### Displacement

It is the distance of the harmonic oscillator from its mean (or equilibrium) position at a given instant.

### Amplitude

It is the maximum displacement of the oscillator on either side of its mean position.

### Time period

It is the time taken by the oscillator to complete one oscillation.

### Frequency

It is the number of oscillations completed by an oscillator in one second. It is denoted by v. The SI unit of frequency is hertz (Hz). Since v is the number of oscillations per second, the time taken to complete one oscillation is 1/v.

T =1/v

### Phase (φ)

It is the angle whose sine or cosine at a given instant indicates the position and direction of motion of the oscillator. It is expressed in radians.

### Angular Frequency (ω)

It describes the rate of change of phase angle. It is expressed in radian per second. Since phase angle changes from 0 to 2π radians in one complete oscillation, the rate of change of phase angle is

ω = 2π/T = 2πv or ω = 2πv