Percobaan Laser | Praktikum Fisika Dasar 2 | UPT Laboratorium Terpadu UHO

Summary

This video explores a laser experiment that demonstrates the unique properties of laser light, such as coherence, collimation, and monochromaticity. The experiment involves three key stages: scattering light, measuring laser beam spread, and observing polarization. In the first stage, participants observe light scattering in water with the help of flour particles. In the second stage, they measure the laser beam's spread and calculate the angle of divergence. The final stage involves using a polarizer to study the effects on laser intensity and direction. Through these steps, participants gain insights into the physical phenomena of laser light and its interactions.

Takeaways

• 😀 Laser is an electromagnetic wave with a very strong intensity and special properties, such as being collimated, meaning the laser beam doesn't lose intensity over long distances.
• 😀 Laser light is coherent, meaning its waves are in phase with each other, and monochromatic, meaning it has a single wavelength, which makes it useful for demonstrating interference phenomena.
• 😀 The experiment consists of three main stages: scattering of light, laser beam spreading, and polarization of light.
• 😀 In the first stage, light scattering is observed by shining laser light through a container of clear water with some powder in it, and the path of the light is observed.
• 😀 In the second stage, the laser beam's spreading is measured by capturing the laser beam with a screen and measuring its diameter at a certain distance.
• 😀 The spreading angle of the laser beam is calculated by dividing the diameter by the distance.
• 😀 In the third stage, the light is polarized by placing a polarizer in front of the laser source, and the laser passes through it.
• 😀 The distance between the laser and the polarizer is adjusted to 20 cm, and the intensity of the laser light is observed after passing through the polarizer.
• 😀 The polarizer's transmission direction is adjusted by rotating it, and the intensity of the laser is observed as the polarizer's orientation changes.
• 😀 Measurements are made using a string to mark the polarization angle, and the results are recorded with a ruler for further analysis, including determining the minimum and maximum intensity of the laser light.

Q & A

What is the main purpose of this laser experiment?

The main purpose of the experiment is for the practitioners to understand the differences between laser light and regular light, and to observe physical phenomena like scattering and polarization of laser light.

What are the key characteristics of laser light?

Laser light is characterized by its high intensity and unique properties, such as being collimated, coherent, and monochromatic. These properties allow laser light to maintain its intensity over long distances and to demonstrate interference phenomena.

What materials and equipment are required for the laser experiment?

The materials and equipment required include a laser source, water tank, screen, flour, polarizer, and thread.

What does the first step of the experiment, light scattering, involve?

In the first step, light scattering is observed by passing the laser beam through a transparent container filled with clear water and capturing the scattered light using a screen. The experiment also involves sprinkling flour in the water and observing the effects.

What is the second step of the laser experiment?

The second step involves measuring the laser beam's spread. A screen is placed in front of the laser source to capture the beam, and its diameter is measured at a specified distance. From this, the scattering angle of the laser is calculated.

How is the laser polarization experiment conducted?

The polarization experiment is conducted by placing a polarizer in front of the laser source and passing the laser through it. The distance between the laser and polarizer is set to 20 cm. The laser beam passing through the polarizer is observed on a screen, and its intensity is measured by rotating the polarizer.

What does rotating the polarizer do in the experiment?

Rotating the polarizer changes the transmission direction of the laser beam, which alters the intensity of the laser light. The intensity variation is then measured, providing insights into the polarization of the light.

What additional measurements are required during the polarization phase?

During the polarization phase, the practitioner is asked to measure the angle of rotation of the polarizer, calculate the minimum and maximum intensity values of the laser on the screen, and measure the diameter of the laser spread on the screen.

What are the steps to follow if the experiment is repeated with a 25 cm polarizer distance?

If the experiment is repeated with a 25 cm polarizer distance, the same steps should be followed: observing the intensity changes by rotating the polarizer, measuring the laser's minimum and maximum intensity, and recording the laser's diameter after spreading.

What is the final goal of the laser experiment?

The final goal of the experiment is to understand the physical phenomena of scattering and polarization in laser light, and to gain insight into how these properties differ from regular light.