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Water Wave

Theme C - Wave Behaviour 

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Rocket

Theme A - Space, Time & Motion

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Thermometer

Theme B - The Particulate Nature Of Matter

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Magnifying Glass Tilted Right

Theme D - Fields

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Microscope

Theme E - Nuclear & Quantum Physics

<ul>
	<li>Like sound waves, light waves and microwaves can interfere. This interference can be observed by shining a single light source through two thin vertical slits, an arrangement known as a double slit.</li>
	<li>The phenomenon was first observed by English physicist and physician Thomas Young in 1801 and is known as double-slit interference or Young&#39;s slit experiment.</li>
</ul>

<ul>
	<li>When a laser or lamp is used to shine light through the two slits, light falls on both slits and creates diffraction patterns.</li>
	<li>If a laser is used, the light is already coherent, meaning the waves are in phase.</li>
	<li>If a lamp is used, a single slit is placed before the double slit, making the light coherent by allowing only a small portion of the wavefront to pass through.</li>
	<li>Each slit emits a cone of diffracted light, which is bounded by the central maximum of the diffraction pattern for that cone.</li>
	<li>The region where the two diffracted beams intersect is where interference can occur. This is because interference requires two beams.</li>
</ul>

<ul>
	<li>When a screen is placed parallel to the plane of the slits in the interference region, a pattern of fringes appears on the screen.</li>
	<li>These fringes, parallel to the orientation of the double slits, show an alternating bright&ndash;dark arrangement with equal spacing on the screen.</li>
	<li>This pattern is similar to the alternating loud and soft regions of sound wave interference.</li>
</ul>

<ul>
	<li>Lasers are important for interference experiments because they emit monochromatic (single-wavelength) and coherent light.</li>
	<li>The theory behind lasers was published by Einstein in 1917, but the first working laser wasn&#39;t made until 1960 by Theodore Maiman.</li>
	<li>Since then, lasers have become cheaper, easier to use, and smaller.</li>
	<li>Lasers are used in applications where interference is important, such as barcode scanners and DVD and CD players.</li>
</ul>

<ul>
	<li>Barcode Scanners: Lasers in barcode scanners use interference to read barcodes accurately. The light emitted is coherent and monochromatic, making it ideal for detecting the alternating black and white bars in a barcode.</li>
	<li>DVD and CD Players: In DVD and CD players, lasers read the data on the disc by detecting changes in the surface. This is done by analyzing the interference pattern created by the reflected laser light.</li>
</ul>

Fun Fact: When Theodore Maiman first made the laser, he described it as &quot;a solution without a problem.&quot; Today, lasers are used in countless applications, from medical surgeries to entertainment shows! So, it seems that this solution found plenty of problems to solve!

Theme C - Wave Behaviour

Unlocking Light Mysteries: The Double-Slit Experiment

Table of content

Interference of light waves

How does it work?

Interference pattern

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Theme C - Wave Behaviour

Unlocking Light Mysteries: The Double-Slit Experiment

Table of content

Interference of light waves

How does it work?

Interference pattern

Unlock the Full Content!