Answer:
The red-shift is the phenomena of the electromagnetic radiation that are emitted from a source that undergoes an increase in wavelength according to the observer.
Step-by-step explanation:
- The red-shift is considered as the Doppler effect in the electromagnetic radiation.
- It is similar to the phenomena of sound waves in the Doppler effect, where the perceived frequency of the electromagnetic radiation emitted by a source tends to increase its wavelength with respect to the observer.
- The red-shift occurs when both, the source and the observer are receding each other.
- If a spectrum of the star or galaxy is red-shifted, it means they are receding from us.
- So, when there is an increase in the wavelength of the emitted spectrum of radiation from the source. It is meant that the source is red-shifted.