Malus's Law and Light Intensity

The lecture covers the behavior of polarized light when passed through an analyzer, focusing on Malus's Law, which states that the intensity of polarized light is proportional to the cosine square of the angle between the light's vibration direction and the analyzer. The lecture explains the relationship between amplitude and intensity, and how to calculate changes in intensity as the analyzer is rotated. It also discusses the angle required to reduce the intensity to half, and concludes with a brief mention of Brewster's Law to be covered in the next lecture.

What happens to light when it passes through an analyzer?

• It becomes unpolarized.

• Its intensity remains unchanged.

• It changes color.

• Its intensity is reduced.

What is the relationship between light intensity and the angle of the analyzer according to Malus's Law?

• Intensity is proportional to sin²θ.

• Intensity is proportional to cos²θ.

• Intensity is proportional to tan²θ.

• Intensity is proportional to θ.

In the context of Malus's Law, what does I₀ represent?

• The maximum intensity of polarized light.

• The initial intensity of unpolarized light.

• The initial amplitude of light.

• The angle of the analyzer.

How is the amplitude of light related to its intensity?

• Intensity is proportional to the square of the amplitude.

• Intensity is proportional to the amplitude.

• Intensity is inversely proportional to the amplitude.

• Intensity is unrelated to the amplitude.

What is the mathematical expression for Malus's Law?

• I = I₀ sin²θ

• I = I₀ tan²θ

• I = I₀ cos²θ

• I = I₀ θ

At what angle does the intensity of polarized light become half according to Malus's Law?

• 30 degrees

• 45 degrees

• 60 degrees

• 90 degrees

What is the value of cosθ when the intensity is halved?

• 1/√2

• 0

• 1/2

• 1

What happens to the intensity of light when the analyzer is rotated by 90 degrees?

• Intensity doubles.

• Intensity becomes zero.

• Intensity remains the same.

• Intensity is halved.

What is the main focus of the next lecture after this one?

• Snell's Law

• Newton's Law

• Brewster's Law

• Malus's Law

Which law helps in understanding the intensity of polarized light after passing through an analyzer?

• Newton's Law

• Hooke's Law

• Malus's Law

• Snell's Law