Which is greater phase or group velocity?
Which is greater phase or group velocity?
The main difference between Phase Velocity and Group Velocity is that phase velocity is greater than the group velocity in a normal medium.
Why can group velocity be greater than c?
By considering a material in which the tail has the opposite sign, it is shown that the group velocity can be larger than c without having any signal propagate faster than c.
Is group velocity greater than velocity of light?
Superluminal group velocities Since the 1980s, various experiments have verified that it is possible for the group velocity (as defined above) of laser light pulses sent through lossy materials, or gainful materials, to significantly exceed the speed of light in vacuum c.
What is the relation between group velocity?
Vg is the group velocity. Vp is the phase velocity. k is the angular wavenumber….Group Velocity and Phase Velocity relation for Dispersive wave non-dispersive wave.
| Type of wave | Condition | Formula |
|---|---|---|
| Dispersive wave | d V p d k ≠ 0 | V p ≠ V g |
| Non-dispersive wave | d V p d k = 0 | V p = V g |
Which is faster group velocity or phase velocity?
But since in the anomalous region the group velocity is faster than the phase velocity, it is no longer equal to the speed of information transfer.
What’s the difference between phase and group velocity?
Phase velocity is defined for both, the single waves and superimposed waves. The group velocity is defined only to the superimposed waves. The group velocity is the velocity of the wave with lower frequency, but the phase velocity is the velocity of the wave with higher frequency.
Can group velocity be greater than phase velocity?
For most substances, therefore, the group velocity is smaller than the phase velocity. In such cases, it is mathematically possible that the group velocity may be larger than the phase velocity.
Which is always greater than free space velocity?
According to theory of special relativity, speed of particle vmatter waves always exceeds c .
Can the group velocity be greater than the speed of light c?
Yes. The group velocity is how fast the wave travels, but he phase velocity is just how fast the wave rises and falls. What happens if you travel faster than the speed of light? According to special relativity, you cannot travel faster than the speed of light.
Is group velocity equal to particle velocity?
Thus, the above equation shows that group velocity is equal to particle velocity.
What is physical significance of group velocity?
The group velocity is just the speed of these wave packets. From the dynamics view, group velocity has a physical significance– the rate of energy transport, which makes it more important than the phase velocity.
What is the difference between group velocity and phase velocity?
