Glossary
Amplitude
The maximum displacement or distance moved by a point on a vibrating body or wave measured from its equilibrium position. It indicates the 'size' of the oscillation.
Example:
When you pull a spring 10 cm from its resting position before releasing it, the amplitude of its oscillation is 10 cm.
Equilibrium Point
The resting position of an oscillating object where the net force acting on it is zero. It is the center of the oscillation.
Example:
For a mass hanging from a spring, the equilibrium point is where the spring's upward force perfectly balances the mass's weight.
Frequency (f)
The number of complete cycles or oscillations that occur per unit of time. It is the reciprocal of the period and is measured in Hertz (Hz).
Example:
If a hummingbird's wings beat 80 times per second, their frequency of oscillation is 80 Hz.
Hooke's Law
A principle stating that the restoring force exerted by a spring is directly proportional to its displacement from equilibrium. The force always acts to return the spring to its equilibrium position.
Example:
When you press down on a bathroom scale, the force exerted by the springs inside follows Hooke's Law, indicating your weight.
Kinetic Energy (K)
The energy an object possesses due to its motion. In SHM, it is maximum at the equilibrium point and zero at maximum displacement.
Example:
A pendulum bob has its greatest kinetic energy as it swings through the very bottom of its arc.
Period (T)
The time it takes for one complete cycle or oscillation of a simple harmonic motion. It is measured in seconds.
Example:
If a swing completes one full back-and-forth motion in 2 seconds, its period is 2 seconds.
Potential Energy (U or Usp)
Stored energy due to an object's position or configuration. For a spring, it's stored when stretched or compressed, maximum at extreme displacements, and zero at equilibrium.
Example:
A stretched slingshot stores potential energy that is converted into kinetic energy when released.
Simple Harmonic Motion (SHM)
A type of periodic motion where the restoring force is directly proportional to the displacement from equilibrium and acts in the opposite direction. It describes oscillations like those of a mass on a spring or a simple pendulum.
Example:
A guitar string vibrating after being plucked exhibits Simple Harmonic Motion, producing a consistent musical note.
Simple Harmonic Oscillator (SHO)
A system that undergoes simple harmonic motion, characterized by a restoring force proportional to the displacement from equilibrium. Examples include mass-spring systems and pendulums.
Example:
A metronome, with its swinging arm, is a classic example of a simple harmonic oscillator used to keep time in music.
Spring Constant (k)
A measure of the stiffness of a spring, representing the force required to stretch or compress it by a unit distance. It is measured in Newtons per meter (N/m).
Example:
A car's suspension system uses springs with a high spring constant to resist large compressions and provide a stable ride.
Total Energy
The sum of the kinetic and potential energies in a system. In an ideal SHM system without friction, the total energy remains constant.
Example:
In a bouncing trampoline, the total energy of the jumper (kinetic + gravitational potential) remains constant if we ignore air resistance and internal energy losses.