Percobaan Interferometer

Summary

This video explains the Michelson interferometer experiment, focusing on the principles of light interference using monochromatic light. It covers the theoretical aspects of wave interference, including constructive and destructive interference, which lead to light and dark fringes. The experiment's setup is described in detail, with components such as a laser, concave lenses, beam splitter, and mirrors, along with precise calibration using a micrometer screw. The interference patterns formed are essential for measuring the wavelength of light, as demonstrated in an example experiment using 500 nm green light at the University of PGRI Semarang.

Takeaways

• 😀 Monochromatic light is key in the Michelson Interferometer experiment, as it consists of light with a single wavelength.
• 😀 Light is an electromagnetic wave with electric (E) and magnetic (B) fields that are perpendicular to each other and to the direction of wave propagation.
• 😀 Interference occurs when two light waves combine, and it can be constructive (intensity increases) or destructive (intensity decreases).
• 😀 In constructive interference, the waves are in phase, amplifying each other, leading to a brighter light pattern.
• 😀 In destructive interference, the waves are out of phase (e.g., delayed by half a wavelength), resulting in zero intensity or a dark spot.
• 😀 The Michelson Interferometer experiment involves a beam splitter that divides the light into two paths, reflecting off mirrors before recombining.
• 😀 When the mirrors are at equal distances, no interference pattern is observed, but slight adjustments create alternating dark and light bands.
• 😀 Adjusting the movable mirror shifts the interference pattern, with the central spot changing from dark to bright or vice versa.
• 😀 The interference pattern on the screen consists of alternating dark and bright bands, forming when the light waves are either in phase or out of phase.
• 😀 The Michelson Interferometer can be used to measure the wavelength of light very precisely, as demonstrated with a green light source of 500 nanometers.
• 😀 The experiment demonstrates the wave nature of light and is essential for various scientific and engineering applications.

Q & A

What is the main purpose of the interferometer experiment discussed in the script?

The main purpose of the interferometer experiment is to demonstrate the concept of light interference, which can be used to measure the wavelength of light by observing the patterns of constructive and destructive interference.

What is monochromatic light, and why is it important in the interferometer experiment?

Monochromatic light refers to light that has a single wavelength. It is important in the interferometer experiment because its consistent wavelength allows for the precise measurement of interference patterns, which are key to determining the properties of the light source.

What are the two components of an electromagnetic wave as explained in the script?

The two components of an electromagnetic wave are the electric field and the magnetic field. The electric field is oriented vertically, and the magnetic field is oriented horizontally, with both fields being perpendicular to the direction of wave propagation.

What is the difference between constructive and destructive interference?

Constructive interference occurs when two waves meet in phase (their peaks and troughs align), resulting in a higher intensity of light. Destructive interference occurs when two waves meet out of phase (one wave's peak aligns with the other's trough), resulting in a reduced or zero intensity of light.

How does the interferometer create interference patterns?

The interferometer creates interference patterns by splitting light into two beams, which are reflected by mirrors and recombined. The beams may travel different path lengths, causing them to interfere with each other when they are recombined, forming bright and dark fringes based on whether the waves are in phase or out of phase.

What is the role of the beam splitter in the interferometer experiment?

The beam splitter's role is to divide the incoming light into two separate beams. These beams then travel different paths and are recombined to produce interference patterns.

How does moving the mirrors affect the interference pattern?

Moving the mirrors changes the path lengths of the two light beams. If the difference in the path lengths is a half-wavelength or more, it shifts the interference pattern, causing changes in the intensity, such as alternating bright and dark fringes.

What are the main components of the interferometer setup used in the experiment?

The main components of the interferometer setup include a laser (light source), convex lenses (to focus the light), a beam splitter (to divide the light), and mirrors (to reflect and recombine the light). One of the mirrors is adjustable to fine-tune the setup.

What was the wavelength of light used in the interferometer experiment conducted at PGRI University of Semarang?

The wavelength of light used in the interferometer experiment at PGRI University of Semarang was 500 nanometers, which corresponds to green light.

What type of interference pattern is observed when the path length difference is an integer multiple of the light's wavelength?

When the path length difference is an integer multiple of the light's wavelength, constructive interference occurs, leading to a bright fringe. The intensity of the light is maximized at these points.