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6.Two Polarizers Are Oriented at 48^circ to Each Other and Plane -polarized Light Is Incident on Them.If Only 35% of the Light Gets

Вопрос

6.Two polarizers are oriented at 48^circ to each other and plane -polarized light is incident on them.If only 35% of the light gets through both of them, what was the initial polarization direction of the incident light ()

Решения

4.2 (270 Голоса)
Эмир
Экспертная проверка
профессионал · Репетитор 6 лет

Ответ

To find the initial polarization direction of the incident light, we need to consider the Malus's law, which relates the intensity of light after passing through a polarizer to the angle between the polarization direction of the incident light and the axis of the polarizer.Malus's law is given by: where:- is the intensity of the light after passing through the polarizer,- is the initial intensity of the light,- is the angle between the polarization direction of the incident light and the axis of the polarizer.In this case, we are given that only 35% of the light gets through both polarizers. This means that the intensity of the light after passing through both polarizers is 35% of the initial intensity.Let's denote the initial polarization direction of the incident light as . The light first passes through a polarizer oriented at an angle of to the incident polarization direction, and then through a second polarizer oriented at an angle of to the first polarizer.Using Malus's law for the first polarizer, we have: Using Malus's law for the second polarizer, we have: Substituting the expression for from the first equation into the second equation, we get: We are given that , so we can substitute this into the equation: Dividing both sides by , we get: To find the value of , we need to solve this equation. Taking the square root of both sides, we get: Dividing both sides by \( \cos(48^\circ) \), we get: Finally, taking the inverse cosine of both sides, we get: Calculating this value, we find that is approximately . Therefore, the initial polarization direction of the incident light was relative to the axis of the first polarizer.