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Ch 34: Ray Optics
Knight Calc - Physics for Scientists and Engineers 5th Edition
Knight Calc5th EditionPhysics for Scientists and EngineersISBN: 9780137344796당신이 사용하는 게 아니라요?교과서 변경
34장, 문제 69

CALC A converging lens with focal length f creates a real image of an object. What is the minimum possible distance between the object and its image? Your answer will be a multiple of f.

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1
Start by recalling the lens equation: 1f = 1do + 1di, where f is the focal length, do is the object distance, and di is the image distance.
To find the minimum possible distance between the object and its image, define the total distance as D = do + di. Substitute di from the lens equation into this expression.
Rearrange the lens equation to express di in terms of do: di = dof / (do - f). Substitute this into D.
Simplify the expression for D to find a single equation in terms of do and f. Then, differentiate D with respect to do to find the critical points.
Solve the derivative equation to find the value of do that minimizes D. Use this value to calculate the minimum distance D in terms of f.

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주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Converging Lens

A converging lens, or convex lens, is a transparent optical device that bends light rays inward to a focal point. It has a positive focal length and is used to form real images when the object is placed outside its focal length. The behavior of light through a converging lens is governed by the lens formula, which relates the object distance, image distance, and focal length.
추천 영상:
가이드 코스
07:58
Thin Lens Equation

Lens Formula

The lens formula is a mathematical relationship that describes the relationship between the object distance (u), image distance (v), and focal length (f) of a lens. It is expressed as 1/f = 1/v + 1/u. This formula is essential for determining the positions of the object and image in relation to the lens, particularly when calculating distances in optical systems.
추천 영상:
가이드 코스
05:38
Lens Maker Equation

Real Image

A real image is formed when light rays converge and can be projected onto a screen. In the case of a converging lens, a real image occurs when the object is placed outside the focal length. The characteristics of a real image include being inverted and having a distance from the lens that can be calculated using the lens formula, which is crucial for determining the minimum distance between the object and its image.
추천 영상:
가이드 코스
03:41
Ideal vs Real Fluids
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