Pulse vs Wave
Waves are a very common occurrence in nature. The origin of waves lies in the vibrations. A sudden change in the energy of a system or an object results in an immediate change, in the energy of the surroundings. This energy dissipates through the medium by different mechanisms to restore the equilibrium. If the process occurs repeatedly, it is known as an oscillation, and the oscillations lead to waves.
In physics, a sudden variation in a quantity that is a constant usually is known as a pulse. This term often refers to a change in position in a medium, seen and described as amplitude, due to a vibration. A series of such sudden variations is also known as a pulse.
A periodic disturbance in a medium or space is known as a wave. The disturbance can be regular or irregular. Waves are the main method of energy transfer in the nature. Whenever excess energy is released from a system or object, it is carried away by a wave. A wave that is carrying energy from a point to another is known as a progressive wave. In some cases, when two waves are confined to a small space, due to interference of these two waves standing waves are created. As a result, the total energy of the wave remains stationary; therefore, such a wave cannot transmit energy.
Waves can also be classified into mechanical waves and electromagnetic waves. Mechanical waves propagate using the oscillation in potential energy and kinetic energy of the particles of the medium. Electromagnetic waves propagate using the alternating oscillations of electric and magnetic fields. Therefore, EM waves require no medium for propagation; hence can travel through empty space.
If the oscillations are perpendicular to the plane of propagation, the waves are known as transverse waves. Water waves and electromagnetic waves are transverse waves. The waves with oscillations occurring parallel to the direction of propagation is known as longitudinal waves. Sound waves and seismic waves are examples of longitudinal waves.
Independent of the type of wave, a wave possesses the properties frequency (f), wavelength (λ)and speed (v). These quantities are related to each other by a simple formula
v = fλ
Frequency is a characteristic of a wave, and the speed of a wave is determined by the properties of the medium. Therefore, wavelength of a wave is determined by the speed of the wave in the medium and the frequency of the wave. Amplitude also is a property of the wave, which is a measure of the strength or the energy stored in the wave. The movement of wave in space is precisely described by the wave equation.
Furthermore, waves undergo physical phenomena known as reflection, refraction, diffraction, and interference.
What is the difference between a Pulse and a Wave?
• A single sudden change in a property of a medium or a quantity is known as a pulse, whereas waves are repeated oscillating changes in the properties or the quantity.
• A pulse has a sharp rise and a sharp decline of amplitude, whereas a wave can be either regular or irregular. The shape of the wave throughout a period is known as waveform.
• A wave can be considered as a series of pulses.