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Ch 34: Ray Optics
Knight Calc - Physics for Scientists and Engineers 5th Edition
Knight Calc5th EditionPhysics for Scientists and EngineersISBN: 9780137344796Not the one you use?Change textbook
Chapter 34, Problem 9

It is 165 cm from your eyes to your toes. You're standing 200 cm in front of a tall mirror. How far is it from your eyes to the image of your toes?

Verified step by step guidance
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Step 1: Understand the problem. The distance from your eyes to your toes is 165 cm, and you are standing 200 cm in front of a mirror. The goal is to determine the distance from your eyes to the image of your toes formed in the mirror.
Step 2: Recall the principle of image formation in a plane mirror. The image of an object in a plane mirror appears to be the same distance behind the mirror as the object is in front of it. This means the image of your toes will be 200 cm behind the mirror.
Step 3: Calculate the total distance from your eyes to the image of your toes. This distance is the sum of the distance from your eyes to the mirror (200 cm) and the distance from the mirror to the image of your toes (200 cm), plus the distance from your eyes to your toes (165 cm).
Step 4: Write the total distance mathematically as: \( \text{Total Distance} = 200 \text{ cm} + 200 \text{ cm} + 165 \text{ cm} \).
Step 5: Add the distances together to find the total distance. This will give you the distance from your eyes to the image of your toes.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Reflection in Mirrors

When light rays hit a mirror, they reflect off the surface according to the law of reflection, which states that the angle of incidence equals the angle of reflection. This means that the image formed in a mirror appears to be the same distance behind the mirror as the object is in front of it. Understanding this principle is crucial for determining the distance from your eyes to the image of your toes.
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Distance Measurement

In this scenario, distance is measured from your eyes to the mirror and from the mirror to the image of your toes. The total distance from your eyes to the image can be calculated by adding the distance from your eyes to the mirror and the distance from the mirror to the image, which is equal to the distance from the mirror to your toes. This concept is fundamental for solving the problem accurately.
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Geometry of Images

The geometry of images in mirrors involves understanding how the position of an object relates to its image. In a flat mirror, the image appears to be the same size as the object and is located directly behind the mirror at an equal distance. This geometric relationship helps in visualizing and calculating the distance from your eyes to the image of your toes in the given scenario.
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