When Interference Occurs - Coherent Sources

Occurrence of Interference-Coherent Source

Introduction

• Interference can occur not only with a single source of waves but also with two sources of waves.
• For interference to happen between two sources, they must satisfy specific conditions.

Coherent Sources

• Interference between two sources of waves is possible when the following conditions are met:
  • There is a constant phase relationship between the sources.
  • The sources have the same frequency, ensuring they maintain a constant phase relationship.
• Such sources of waves that meet these conditions are called coherent sources.

Constant Phase Relationship

• To achieve interference, it's crucial that the waves from both sources maintain a consistent phase relationship.
• Phase refers to the position of a point on a wave cycle at a particular moment.
• The phase relationship ensures that the crests and troughs of the waves from the two sources coincide or align predictably.

Same Frequency

• Coherent sources must emit waves with the same frequency.
• Frequency determines the number of wave cycles per unit of time.
• When two sources have the same frequency, they create waves that maintain the same temporal pattern, facilitating interference.

Applications

• Coherent sources and interference are essential concepts in various fields, including optics, where lasers employ coherent light sources for applications such as holography and interferometry.
• In optics, coherent sources of light produce interference patterns that reveal information about the objects they interact with.

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Physics

When Interference Occurs - Coherent Sources

Key Points

• Interference can also occur with two sources of waves.
• For interference to happen between two sources, they must be coherent.
• Coherent sources have a constant phase relationship and the same frequency.

Summary

• Interference can take place between two sources of waves when they are coherent, meaning they maintain a constant phase relationship and have the same frequency.
• Coherent sources are crucial in applications like optics, where they are used in lasers for various purposes, including holography and interferometry.