Skip to main content
Ch 34: Ray Optics
Knight Calc - Physics for Scientists and Engineers 5th Edition
Knight Calc5th EditionPhysics for Scientists and EngineersISBN: 9780137344796Non è quello che usi tu?Cambia libro di testo
Capitolo 34, Problema 47a

A light ray in air is incident on a transparent material whose index of refraction is n. Find an expression for the (non-zero) angle of incidence whose angle of refraction is half the angle of incidence.

Guida verificata passo dopo passo
1
Start by applying Snell's Law, which relates the angles of incidence and refraction to the indices of refraction of the two media: n1⁢sin⁢θ1=n2⁢sin⁢θ2. Here, n1 is the index of refraction of air (approximately 1), n2 is the index of refraction of the material (n), θ1 is the angle of incidence, and θ2 is the angle of refraction.
Substitute the given condition that the angle of refraction is half the angle of incidence: θ2=θ12. This means sin⁢θ2=sin⁢θ12.
Using the trigonometric identity for the sine of a half-angle, rewrite sin⁢θ12 as 12⁢(1-cos⁢θ1).
Substitute this expression for sin⁢θ2 into Snell's Law: sin⁢θ1=n⁢12⁢(1-cos⁢θ1).
Square both sides of the equation to eliminate the square root, and solve for cos⁢θ1. This will give you an expression for the angle of incidence θ1 in terms of the index of refraction n.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Snell's Law

Snell's Law describes the relationship between the angles of incidence and refraction when a light ray passes between two different media. It is mathematically expressed as n1 * sin(θ1) = n2 * sin(θ2), where n1 and n2 are the indices of refraction of the two media, and θ1 and θ2 are the angles of incidence and refraction, respectively.
Video consigliato:

Index of Refraction

The index of refraction (n) is a dimensionless number that describes how much light slows down when it enters a material compared to its speed in a vacuum. It is defined as n = c/v, where c is the speed of light in a vacuum and v is the speed of light in the material. A higher index indicates that light travels slower in that medium.
Video consigliato:
Percorso guidato
03:46
Index of Refraction

Angle Relationships

In the context of the problem, the relationship between the angle of incidence (θ1) and the angle of refraction (θ2) is crucial. The question specifies that θ2 is half of θ1, which can be expressed as θ2 = θ1/2. This relationship will be used in conjunction with Snell's Law to derive the expression for the angle of incidence.
Video consigliato:
Percorso guidato
03:43
Relationships Between Force, Field, Energy, Potential
Pratica correlata
Domanda del libro di testo

A 4.0-m-wide swimming pool is filled to the top. The bottom of the pool becomes completely shaded in the afternoon when the sun is 20° above the horizon. How deep is the pool?

1622
views
Domanda del libro di testo

An advanced computer sends information to its various parts via infrared light pulses traveling through silicon fibers. To acquire data from memory, the central processing unit sends a light-pulse request to the memory unit. The memory unit processes the request, then sends a data pulse back to the central processing unit. The memory unit takes 0.5 ns to process a request. If the information has to be obtained from memory in 2.0 ns, what is the maximum distance the memory unit can be from the central processing unit?

74
views
Domanda del libro di testo

The place you get your hair cut has two nearly parallel mirrors 5.0 m apart. As you sit in the chair, your head is 2.0 m from the nearer mirror. Looking toward this mirror, you first see your face and then, farther away, the back of your head. (The mirrors need to be slightly nonparallel for you to be able to see the back of your head, but you can treat them as parallel in this problem.) How far away does the back of your head appear to be? Neglect the thickness of your head.

97
views
Domanda del libro di testo

The 80-cm-tall, 65-cm-wide tank shown in FIGURE P34.48 is completely filled with water. The tank has marks every 10 cm along one wall, and the 0 cm mark is barely submerged. As you stand beside the opposite wall, your eye is level with the top of the water. Can you see the marks from the top of the tank (the 0 cm mark) going down, or from the bottom of the tank (the 80 cm mark) coming up? Explain.


103
views
Domanda del libro di testo

A horizontal meter stick is centered at the bottom of a 3.0-m-deep, 3.0-m-wide pool of water. Suppose you place your eye just above the edge of the pool and look along the direction of the meter stick. What angle do you observe between the two ends of the meter stick if the pool is (a) empty and (b) completely filled with water?

71
views
Domanda del libro di testo

A red ball is placed at point A in FIGURE P34.44. What are the (x, y) coordinates of each image?

141
views